Baker percentage

Last updated

Baker's percentage is a notation method indicating the proportion of an ingredient relative to the flour used in a recipe when making breads, cakes, muffins, and other baked goods. [1] [2] [3] [4] It is also referred to as baker's math, [5] [6] and may be indicated by a phrase such as based on flour weight. [1] [7] It is sometimes called formula percentage, [1] a phrase that refers to the sum of a set of baker's percentages. [note 1] Baker's percentage expresses a ratio in percentages of each ingredient's weight to the total flour weight: [10] [12] [13]

Contents

For example, in a recipe that calls for 10 pounds of flour and 5 pounds of water, the corresponding baker's percentages are 100% for the flour and 50% for the water. Because these percentages are stated with respect to the weight of flour rather than with respect to the weight of all ingredients, the sum of these percentages always exceeds 100%.

Flour-based recipes are more precisely conceived as baker's percentages, and more accurately measured using weight instead of volume. The uncertainty in using volume measurements follows from the fact that flour settles in storage and therefore does not have a constant density. [14] [15]

Baker's percentages

A yeast-dough formula could call for the following list of ingredients, presented as a series of baker's percentages:

flour 100% 
water60%
yeast1%
salt2%
oil1%

Conversions

There are several common conversions that are used with baker's percentages. Converting baker's percentages to ingredient weights is one. Converting known ingredient weights to baker percentages is another. Conversion to true percentages, or based on total weight, is helpful to calculate unknown ingredient weights from a desired total or formula weight.

Using baker's percentages

To derive the ingredient weights when any weight of flour Wf is chosen: [note 2]

Digital scale for weighing ingredients. Waga elektroniczna.jpg
Digital scale for weighing ingredients.
Baker's
percentage		weights
[note 3]
ingredient  %method 1method 2
flour 100%  Wf * 1.00 Wf * 100%
water35% Wf * 0.35 Wf * 35%
milk35% Wf * 0.35 Wf * 35%
fresh yeast4% Wf * 0.04 Wf * 4%
salt1.8% Wf * 0.018  Wf * 1.8%

In the example below, 2 lb and 10 kg of flour weights have been calculated. Depending on the desired weight unit, only one of the following four weight columns is used:

Weighing ingredients. 1 pesee.jpg
Weighing ingredients.
Baker's
percentage		weights
2 lb10 kg
ingredient  %lbozkgg
flour 100% 23210 10000 
water35%0.711.23.53500
milk35%0.711.23.53500
fresh yeast4%0.081.280.4400
salt1.8% 0.036  0.576  0.18 180

Creating baker's percentages

The baker has determined how much a recipe's ingredients weigh, and uses uniform decimal weight units. All ingredient weights are divided by the flour weight to obtain a ratio, then the ratio is multiplied by 100% to yield the baker's percentage for that ingredient:

Using a balance to measure a mass of flour. US Navy 111220-N-OY799-007 Culinary Specialist Seaman Matthew Ryback measures flour in preparation for the Christmas meal in the bake shop aboard t.jpg
Using a balance to measure a mass of flour.
ingredient  weight  ingredient mass⁄flour mass × 100%
flour10 kg10 kg ÷ 10 kg = 1.000=100%
water3.5 kg3.5 kg ÷ 10 kg = 0.350=35%
milk3.5 kg3.5 kg ÷ 10 kg = 0.350=35%
fresh yeast0.4 kg0.4 kg ÷ 10 kg = 0.040=4%
salt0.18 kg0.18 kg ÷ 10 kg = 0.018=1.8%

Due to the canceling of uniform weight units, the baker may employ any desired system of measurement (metric or avoirdupois, [16] etc.) when using a baker's percentage to determine an ingredient's weight. Generally, the baker finds it easiest to use the system of measurement that is present on the available tools.

Formula percentage and total mass

Ingredient
[note 4] 		baker's
%		true
%
flour 100%  56.88% 
water35%19.91%
milk35%19.91%
fresh yeast 4%2.28%
salt1.8%1.02%
Total175.8%100%

The total or sum of the baker's percentages is called the formula percentage. The sum of the ingredient masses is called the formula mass (or formula "weight"). Here are some interesting calculations:

  • The flour's mass times the formula percentage equals the formula mass: [11]
  • An ingredient's mass is obtained by multiplying the formula mass by that ingredient's true percentage; because an ingredient's true percentage is that ingredient's baker's percentage divided by the formula percentage expressed as parts per hundred, an ingredient's mass can also be obtained by multiplying the formula mass by the ingredient's baker's percentage and then dividing the result by the formula percentage:
Thus, it is not necessary to calculate each ingredient's true percentage in order to calculate each ingredient's mass, provided the formula mass and the baker's percentages are known.
  • Ingredients' masses can also be obtained by first calculating the mass of the flour then using baker's percentages to calculate remaining ingredient masses:
  • The two methods of calculating the mass of an ingredient are equivalent:

Weights and densities

The use of customary U.S. units can sometimes be awkward and the metric system makes these conversions simpler. In the metric system, there are only a small number of basic measures of relevance to cooking: the gram (g) for weight, the liter (L) for volume, the meter (m) for length, and degrees Celsius (°C) for temperature; multiples and sub-multiples are indicated by prefixes, two commonly used metric cooking prefixes are milli- (m-) and kilo- (k-). [17] Intra-metric conversions involve moving the decimal point. [18]

Common avoirdupois and metric weight equivalences: [19]

1 pound (lb) = 16 ounces (oz)
1 kilogram (kg) = 1,000 grams (g) = 2.20462262 lb
1 lb = 453.59237 g = 0.45359237 kg
1 oz = 28.3495231 g.

In four different English-language countries of recipe and measuring-utensil markets, approximate cup volumes range from 236.59 to 284.1 milliliters (mL). Adaptation of volumetric recipes can be made with density approximations:

Volume to mass conversions for some common cooking ingredients
ingredientdensity
g/mL
[note 5] 		metric cup
250 mL		imperial cup
≈284 mL		U.S. customary cup
≈237 mL [note 6]
gozgozgoz
water [note 7] 1 [note 8] 249–2508.8283–28410236–2378.3 [note 9]
granulated sugar0.8 [20] 2007.02308.01906.7
wheat flour0.5–0.6 [20] 120–1504.4–5.3140–1705.0–6.0120–1404.2–5.0
table salt1.2 [20] 30010.634012.028010.0

Due to volume and density ambiguities, a different approach involves volumetrically measuring the ingredients, then using scales or balances of appropriate accuracy and error ranges to weigh them, and recording the results. With this method, occasionally an error or outlier of some kind occurs.

Drawbacks

Baker's percentages do not accurately reflect the impact of the amount of gluten-forming proteins in the flour on the final product and therefore may need to be adjusted from country to country, or even miller to miller, depending on definitions of terms like "bread flour" and actual protein content. [21] Manipulation of known flour-protein levels can be calculated with a Pearson square. [22] [23]

Digital scale with readability of 0.01 g. Feinwaage messend.jpg
Digital scale with readability of 0.01 g.

In home baking, the amounts of ingredients such as salt or yeast expressed by mass may be too small to measure accurately on the scales used by most home cooks. For these ingredients, it may be easier to express quantities by volume, based on standard densities. For this reason, many breadmaking books that are targeted to home bakers provide both percentages and volumes for common batch sizes.

Besides the need for appropriate readability scales, a kitchen calculator is helpful when working directly from baker's percentages.

Advantages

Baker's percentages enable the user to:

Common formulations

Common formulations for bread [24] include 100% flour, 60% water/liquid, 1% yeast, 2% salt and 1% oil, lard or butter.

Dough hydration

A dough with very high hydration High hydration dough.jpg
A dough with very high hydration

In a recipe, the baker's percentage for water is referred to as the "hydration"; it is indicative of the stickiness of the dough and the "crumb" of the bread. Lower hydration rates (e.g., 50–57%) are typical for bagels and pretzels, and medium hydration levels (58–65%) are typical for breads and rolls. [25] Higher hydration levels are used to produce more and larger holes, as is common in artisan breads such as baguettes or ciabatta. Doughs are also often classified by the terms stiff, firm, soft, and slack. [26] Batters are more liquid doughs. Muffins are a type of drop batter while pancakes are a type of pour batter.

Doughs
[25] [26]
Very stiff< 57%
Stiff to firm57-65%
Soft65-70%
Soft to slack70-80%
Batters
[note 10]
Drop95%
Pour190%

Notes

  1. ↑ There is some ambiguity regarding the use of the phrase "formula percentage" in the literature. From the published date of 2004 [8] to the date 2007, [9] Hui's definitions have changed slightly. In 2004 "formula percent" was defined by "total weight of all ingredients"; however by the latter date's usage, the preference was to use the prefix "true" in the phrase "True formula percent (true percent)" when referring to "total weight of all ingredients." In 2005, Ramaswamy & Marcotte used the phrase "typical formula" in reference to a "baker's %" series of ingredients, then drew the semantic and mathematic distinctions that "actual percentage" was one based upon "total mass", which they labeled "% flour", "% water", etc. [10] In 2010, Figoni said that "baker's percentage" was "sometimes called formula percentage...." [1] In 1939, the phrase formula percentage was said to commonly refer to the sum of the particular percentages that would later be called bakers' percentages. [11]
  2. ↑ Derived algebraically from Gisslen's formula.
  3. ↑ Wf denotes a flour weight. In method 1 the percentage was divided by 100%. Method 2 works well when using a calculator. When using a spreadsheet, formatting the cell as percentage versus number automatically handles the per-cent portion of the calculation.
  4. ↑ True percentage values have been rounded and are approximate.
  5. ↑ One gram per millilitre is very close to one avoirdupois ounce per fluid ounce: 1 g/mL ≈ 1.002 av oz/imp fl oz This is not a numerical coincidence, but comes from the original definition of the kilogram as the mass of one litre of water, and the imperial gallon as the volume occupied by ten avoirdupois pounds of water. The slight difference is due to water at 4 °C (39 °F) being used for the kilogram, and at 62 °F (17 °C) for the imperial gallon. The U.S. fluid ounce is slightly larger.
    1 g/mL ≈ 1.043 av oz/U.S. fl oz
  6. ↑ From cup (unit). Note the similarity of cup mL to water weight or mass as g. This density relationship can also be useful for determining unknown volumes.
  7. ↑ 1 g/mL is a good rough guide for water-based liquids such as milk (the density of milk Archived 2011-08-05 at the Wayback Machine is about 1.03–1.04 g/mL).
  8. ↑ The density of water ranges from about 0.96 to 1.00 g/mL dependent on temperature and pressure. The table above assumes a temperature range 0–30 °C (32–86 °F). The variation is too small to make any difference in cooking.
  9. ↑ Since an imperial cup of water weighs approximately 10 avoirdupois ounces and five imperial cups are approximately equal to six U.S. cups, one U.S. cup of water weighs approximately 8⅓ avoirdupois ounces.
  10. ↑ Mathematically converted from liquid-to-dry volumetric ratios on quick bread. 1 cup water weighs 237 g, 1 cup all purpose flour, 125 g, rounding applied. It is worth noting that if the liquid is whole milk of 3.25% milkfat, which is somewhat common in pancake recipes, the actual water content or hydration is about 88% of that value per the USDA National Nutrient database, thus pancake hydrations may be as low as, or lower than, 167% or thereabouts (190% * 88%).

Related Research Articles

<span class="mw-page-title-main">Bread</span> Food made of flour and water

Bread is a staple food prepared from a dough of flour and water, usually by baking. Throughout recorded history and around the world, it has been an important part of many cultures' diet. It is one of the oldest human-made foods, having been of significance since the dawn of agriculture, and plays an essential role in both religious rituals and secular culture.

<span class="mw-page-title-main">Cooking weights and measures</span> Specifications for quantities of ingredients

In recipes, quantities of ingredients may be specified by mass, by volume, or by count.

<span class="mw-page-title-main">Pastry</span> Various baked products made of dough

Pastry refers to a variety of doughs, as well as the sweet and savoury baked goods made from them. These goods are often called pastries as a synecdoche, and the dough may be accordingly called pastry dough for clarity. Sweetened pastries are often described as bakers' confectionery. Common pastry dishes include pies, tarts, quiches, croissants, and pasties.

<span class="mw-page-title-main">Baking powder</span> Dry chemical leavening agent

Baking powder is a dry chemical leavening agent, a mixture of a carbonate or bicarbonate and a weak acid. The base and acid are prevented from reacting prematurely by the inclusion of a buffer such as cornstarch. Baking powder is used to increase the volume and lighten the texture of baked goods. It works by releasing carbon dioxide gas into a batter or dough through an acid–base reaction, causing bubbles in the wet mixture to expand and thus leavening the mixture. The first single-acting baking powder was developed by food manufacturer Alfred Bird in England in 1843. The first double-acting baking powder, which releases some carbon dioxide when dampened and later releases more of the gas when heated by baking, was developed by Eben Norton Horsford in the U.S. in the 1860s.

<span class="mw-page-title-main">Baker's yeast</span> Yeast used as a leavening agent in baking

Baker's yeast is the common name for the strains of yeast commonly used in baking bread and other bakery products, serving as a leavening agent which causes the bread to rise by converting the fermentable sugars present in the dough into carbon dioxide and ethanol. Baker's yeast is of the species Saccharomyces cerevisiae, and is the same species as the kind commonly used in alcoholic fermentation, which is called brewer's yeast or the deactivated form nutritional yeast. Baker's yeast is also a single-cell microorganism found on and around the human body.

<span class="mw-page-title-main">Baker</span> Person who bakes and optionally sells bread products

A baker is a tradesperson who bakes and sometimes sells breads and other products made of flour by using an oven or other concentrated heat source. The place where a baker works is called a bakery.

<span class="mw-page-title-main">Dough</span> Paste used in cooking

Dough is a thick, malleable, sometimes elastic paste made from grains or from leguminous or chestnut crops. Dough is typically made by mixing flour with a small amount of water or other liquid and sometimes includes yeast or other leavening agents, as well as ingredients such as fats or flavorings.

<span class="mw-page-title-main">Soda bread</span> Wheat bread leavened with baking soda

Soda bread is a variety of quick bread made in many cuisines in which sodium bicarbonate is used as a leavening agent instead of yeast. The basic ingredients of soda bread are flour, baking soda, salt, and buttermilk. The buttermilk contains lactic acid, which reacts with the baking soda to form bubbles of carbon dioxide. Other ingredients can be added, such as butter, egg, raisins, or nuts. Quick breads can be prepared quickly and reliably, without requiring the time and labor needed for kneaded yeast breads.

<span class="mw-page-title-main">Bread machine</span> Type of home appliance for baking bread

A bread making machine or breadmaker is a home appliance for baking bread. It consists of a bread pan, at the bottom of which are one or more built-in paddles, mounted in the center of a small special-purpose oven. The machine is usually controlled by a built-in computer using settings input via a control panel. Most bread machines have different cycles for different kinds of dough—including white bread, whole grain, European-style, and dough-only. Many also have a timer to allow the bread machine to function without operator input, and some high-end models allow the user to program a custom cycle.

<span class="mw-page-title-main">Quick bread</span> Bread leavened with agents other than yeast

Quick bread is any bread leavened with a chemical leavening agent rather than a biological one like yeast or sourdough starter. An advantage of quick breads is their ability to be prepared quickly and reliably, without requiring the time-consuming skilled labor and the climate control needed for traditional yeast breads.

<span class="mw-page-title-main">Rye bread</span> Type of bread made with various proportions of flour from rye grain

Rye bread is a type of bread made with various proportions of flour from rye grain. It can be light or dark in color, depending on the type of flour used and the addition of coloring agents, and is typically denser than bread made from wheat flour. Compared to white bread, it is higher in fiber, darker in color, and stronger in flavor. The world's largest exporter of rye bread is Poland.

<span class="mw-page-title-main">Kneading</span> Process of preparing dough

In cooking, kneading is a process in the making of bread or dough, used to mix the ingredients and add strength to the final product. It allows the process of baking to be shortened by developing the gluten more quickly than it would develop in the absence of kneading.

<span class="mw-page-title-main">Cup (unit)</span> Cooking measure of volume

The cup is a cooking measure of volume, commonly associated with cooking and serving sizes. In the US, it is traditionally equal to one-half US pint (236.6 ml). Because actual drinking cups may differ greatly from the size of this unit, standard measuring cups may be used, with a metric cup being 250 millilitres.

<span class="mw-page-title-main">Pre-ferment</span> Process in some methods of bread making

A ferment is a fermentation starter used in indirect‍ methods of bread making. It may also be called mother dough.

<span class="mw-page-title-main">Proofing (baking technique)</span> Process by which a yeast-leavened dough rises

In cooking, proofing is a step in the preparation of yeast bread and other baked goods in which the dough is allowed to rest and rise a final time before baking. During this rest period, yeast ferments the dough and produces gases, thereby leavening the dough.

The sponge and dough method is a two-step bread making process: in the first step a sponge is made and allowed to ferment for a period of time, and in the second step the sponge is added to the final dough's ingredients, creating the total formula. In this usage, synonyms for sponge are yeast starter or yeast pre-ferment. In French baking the sponge and dough method is known as levain-levure. The method is reminiscent of the sourdough or levain methods; however, the sponge is made from all fresh ingredients prior to being used in the final dough.

<span class="mw-page-title-main">Biscuit (bread)</span> Type of bread

In the United States, a biscuit is a variety of baked bread with a firm, dry exterior and a soft, crumbly interior. In Canada it sometimes also refers to this or a traditional European biscuit. It is made with baking powder as a leavening agent rather than yeast, and at times is called a baking powder biscuit to differentiate it from other types. Like other forms of bread, a biscuit is often served with butter or other condiments, flavored with other ingredients, or combined with other types of food to make sandwiches or other dishes.

<span class="mw-page-title-main">No-knead bread</span> Bread made from dough that is not kneaded

No-knead bread is a method of bread baking that uses a very long fermentation (rising) time instead of kneading to form the gluten strands that give the bread its texture. It is characterized by a low yeast content and a very wet dough.

<span class="mw-page-title-main">Straight dough</span> Bread making process

Straight dough is a single-mix process of making bread. The dough is made from all fresh ingredients, and they are all placed together and combined in one kneading or mixing session. After mixing, a bulk fermentation rest of about 1 hour or longer occurs before division. It is also called the direct dough method.

<i>English Bread and Yeast Cookery</i> 1977 English cookery book

English Bread and Yeast Cookery is an English cookery book by Elizabeth David, first published in 1977. The work consists of a history of bread-making in England, improvements to the process developed in Europe, an examination of the ingredients used and recipes of different types of bread.

References

  1. 1 2 3 4 Paula I. Figoni (2010). How Baking Works: Exploring the Fundamentals of Baking Science. New York: Wiley. pp. 9–11. ISBN   978-0-470-39267-6 . Retrieved 2010-12-06. Baker's percentage—sometimes called formula percentage or indicated as "on flour weight basis"—is different from the percentages commonly taught in math classes.
  2. 1 2 Griffin, Mary Annarose; Gisslen, Wayne (2005). Professional baking (4th ed.). New York: John Wiley. p. 10. ISBN   0-471-46427-9 . Retrieved 2011-01-01.
  3. 1 2 Corriher, Shirley (2008). BakeWise: The Hows and Whys of Successful Baking with Over 200 Magnificent Recipes. New York: Scribner. p. 32. ISBN   978-1-4165-6078-4 . Retrieved 2010-12-09.
  4. ↑ Hui, Yiu H. (2006). Handbook of food science, technology, and engineering. Washington, DC: Taylor & Francis. p. 16-6. ISBN   0-8493-9849-5 . Retrieved 2010-12-09.
  5. ↑ Laura Halpin Rinsky; Glenn Rinsky (2009). The pastry chef's companion: a comprehensive resource guide for the baking and pastry professional. Chichester: John Wiley & Sons. p. 19. ISBN   978-0-470-00955-0 . Retrieved 2010-12-09.
  6. ↑ Daniel T. DiMuzio (2009). Bread Baking: An Artisan's Perspective. New York: Wiley. p. 31. ISBN   978-0-470-13882-3 . Retrieved 2010-12-11.
  7. ↑ Cauvain, Stanley P. (2003). Bread making: improving quality. Boca Raton: CRC Press. p. 475. ISBN   1-85573-553-9 . Retrieved 2010-12-08. Generally the taste of yeast itself is not detectable in bread unless the amount of yeast used is greater than 2.5% based on the weight of flour.
  8. ↑ J. Scott Smith; Yiu H. Hui, eds. (2004). Food processing: principles and applications. Cambridge, MA: Blackwell Pub. p. 178. ISBN   0-8138-1942-3 . Retrieved 2010-12-29. Formula—term used instead of "recipe," by the baking industry; the weight of each ingredient is determined based on the weight of flour at 100%.
    Formula percent—term used by the baking industry to describe the amount of each ingredient by weight for a "recipe" or formula compared to the weight of all ingredients.
  9. ↑ Yiu H. Hui, ed. (2007). Handbook of food products manufacturing. New York: Wiley. p. 302. ISBN   978-0-470-12524-3 . Retrieved 2010-12-29. True formula percent (true percent): Term used by the baking industry to describe the amount of each ingredient by weight for a "recipe" or formula compared with the total weight of all ingredients.
  10. 1 2 3 Michele Marcotte; Hosahalli Ramaswamy (2005). Food Processing: Principles and Applications. Boca Raton: CRC. pp. 14–15. ISBN   1-58716-008-0 . Retrieved 2010-12-25.
  11. 1 2 Quartermaster Corps, ed. (1939). Army baker. Washington: U.S. Government Printing Office. pp. 38–41. Training Manual No. 2100-151. Retrieved 2012-02-07. The sum of the percentages of ingredients used in any dough is commonly referred to as the formula percentage (168 percent in example in b above). The sum of the weights of ingredients used in a dough is commonly referred to as formula weight (462 pounds in example in c above).
  12. ↑ Gisslen, Wayne (2007). Professional cooking (Sixth ed.). New York: John Wiley. p. 893. ISBN   978-0-471-66376-8 . Retrieved 2010-12-25.
  13. ↑ Gisslen, Wayne (2009). Professional baking. New York: John Wiley. p. 24. ISBN   978-0-471-78349-7.
  14. ↑ Stanley P. Cauvain (2009). Stanley P. Cauvain; Linda S. Young (eds.). The ICC Handbook of Cereals, Flour, Dough & Product Testing: Methods and Applications. BakeTran, High Wycombe, Buckinghamshire, UK. Lancaster, Pennsylvania: DEStech Publications, Inc. p. 69. ISBN   978-1-932078-99-2 . Retrieved 2010-12-26. Using Cereal Testing at Mill Intake" > "The Bulk Density of Grain (Hectolitre Mass, Bushel Mass, Test Weight, Specific Weight)
  15. ↑ Wihlfahrt, Julius Emil (1913) [1905]. A treatise on flour, yeast, fermentation and baking, together with recipes for bread and cakes. THE FLEISCHMANN CO. p. 25. Retrieved 2010-01-22.
  16. ↑ Rees, Nicole; Amendola, Joseph (2003). The baker's manual: 150 master formulas for baking. London: J. Wiley. p. 11. ISBN   0-471-40525-6 . Retrieved 2010-12-06.
  17. ↑ "The Metric Kitchen". Archived from the original on 2010-12-08. Retrieved 2010-11-30.
  18. ↑ "Intra-metric Conversions". Archived from the original (Doc) on 2006-09-16. Retrieved 2011-02-15.
  19. ↑ Google Calculator, archived from the original on 2019-12-14, retrieved 2010-12-18
  20. 1 2 3 L. Fulton, E. Matthews, C. Davis: Average weight of a measured cup of various foods. Home Economics Research Report No. 41, Agricultural Research Service, United States Department of Agriculture, Washington, DC, 1977.
  21. ↑ "KitchenSavvy: Flour Power?". Archived from the original on 2010-06-14. Retrieved 2010-12-09.
  22. ↑ Hosahalli Ramaswamy; Amalendu Chakraverty; Mujumdar, Arun S.; Vijaya Raghavan (2003). Handbook of postharvest technology: cereals, fruits, vegetables, tea, and spices. New York, N.Y: Marcel Dekker. p. 263. ISBN   0-8247-0514-9 . Retrieved 2010-01-07.
  23. ↑ Van Loon, Dirk (1976). The family cow. Charlotte, Vt: Garden Way Pub. p. 152. ISBN   0-88266-066-7.
  24. ↑ Reinhart, Peter (2009). Peter Reinhart's Artisan Breads Every Day. Berkeley, Calif: Ten Speed Press. pp. 207–209. ISBN   978-1-58008-998-2 . Retrieved 2010-12-09.
  25. 1 2 "SCS 020| Bread Classifications | Stella Culinary". Archived from the original on 2023-01-08. Retrieved 2012-08-25.
  26. 1 2 "Bakers Percentages - Revised". Archived from the original on 2014-12-03. Retrieved 2014-11-28.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.