Barley

Barley
Barley field
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Monocots
(unranked): Commelinids
Order: Poales
Family: Poaceae
Subfamily: Pooideae
Tribe: Triticeae
Genus: Hordeum
Species: H. vulgare[1]
Binomial name
Hordeum vulgare
L. is a cereal grain derived from the annual grass Hordeum vulgare.

Barley is a major cereal grain, a member of the grass family. It serves as a major animal fodder, a source of fermentable material for beer and certain distilled beverages, and as a component of various health foods. It is used in soups and stews, and in barley bread of various cultures.

In a 2007 ranking of cereal crops in the world, barley was fourth both in terms of quantity produced (136 million tons) and in area of cultivation (566,000 km²).[2]

Contents

Etymology

The Old English word for 'barley' was bære, which traces back to Proto-Indo-European and is cognate to the Latin word farina "flour". The direct ancestor of modern English barley in Old English was the derived adjective bærlic, meaning "of barley".[3] The first citation of the form bærlic in the Oxford English Dictionary dates to around 966 AD, in the compound word bærlic-croft.[4] The underived word bære survives in the north of Scotland as bere, and refers to a specific strain of six-row barley grown there.[5][6][7] The word barn, which originally meant barley-house, is also rooted in these words.[3]

Biology

Barley is a member of the grass family. It is a self-pollinating, diploid species with 14 chromosomes. The wild ancestor of domesticated barley, Hordeum vulgare subsp. spontaneum, is abundant in grasslands and woodlands throughout the Fertile Crescent and is abundant in disturbed habitats, roadsides and orchards. Outside this region, the wild barley is less common and is usually found in disturbed habitats.[8]

Domestication

Wild barley has a brittle spike; upon maturity, the spikelets separate, facilitating seed dispersal. Domesticated barley has non-shattering spikes, making it much easier to harvest the mature ears.[8] The non-shattering condition is caused by a mutation in one of two tightly-linked genes known as Bt1 and Bt2; many cultivars possess both mutations. The non-shattering condition is recessive, so varieties of barley that exhibit this condition are homozygous for the mutant allele.[8]

Two-row and six-row barley

Spikelets are arranged in triplets which alternate along the rachis. In wild barley (and other Old World species of Hordeum), only the central spikelet is fertile, while the other two are reduced. This condition is retained in certain cultivars known as two-row barleys. A pair of mutations (one dominant, the other recessive) result in fertile lateral spikelets. This produces six-row barleys. (See Cultivars).[8] Recent genetic studies have revealed a mutation in one gene, vrs1, is responsible for the transition from two-row to six-row barley.[9]

Two-row barley has a lower protein content than six-row barley and thus more fermentable sugar content. High protein barley is best suited for animal feed. Malting barley is usually lower protein[10] ('low grain nitrogen', usually produced without a late fertilizer application) which shows more uniform germination, needs shorter steeping, and has less protein in the extract that can make beer cloudy. Two-row barley is traditionally used in English ale style beers. Six-row barley is common in some American lager style beers, especially when adjuncts such as corn and rice are used, whereas two-row malted summer barley is preferred for traditional German beers.

Hulless or "naked" barley

Hulless or "naked" barley (Hordeum vulgare L. var. nudum Hook. f.) is a form of domesticated barley with an easier to remove hull. Naked barley is an ancient food crop, but a new industry has developed around uses of selected hulless barley in order to increase the digestible energy of the grain, especially for swine and poultry.[11] Hulless barley has been investigated for several potential new applications as whole grain, and for its value-added products. These include bran and flour for multiple food applications.[12]

Classification

In traditional classifications of barley these morphological differences have led to different forms of barley being classified as different species. Under these classifications two-rowed barley with shattering spikes (wild barley) is classified as Hordeum spontaneum K.Koch. Two-rowed barley with non-shattering spikes is classified as H. distichum L., six-rowed barley with non-shattering spikes as H. vulgare L. (or H. hexastichum L.), and six-rowed with shattering spikes as H. agriocrithon Åberg.

The fact that these differences were driven by single-gene mutations, coupled with cytological and molecular evidence, has led most recent classifications to treat these forms as a single species, H. vulgare L.[8]

History

Barley was one of the first domesticated grains in the Fertile Crescent (Near East[13]) which spans the land of present day Iraq, Syria, Palastine, and Lebanon. The grain appeared in the same time as einkorn and emmer wheat.[14] Wild barley (H. vulgare ssp. spontaneum) ranges from North Africa and Crete in the west, to Tibet in the east.[8] The earliest evidence of wild barley in an archaeological context comes from the Epipaleolithic at Ohalo II at the southern end of the Sea of Galilee. The remains were dated to about 8500 BC.[8] The earliest domesticated barley occurs at Aceramic Neolithic sites, in the Near East such as the Pre-Pottery Neolithic B layers of Tell Abu Hureyra, in Syria. Barley has been grown in the Korean Peninsula since the Early Mumun Pottery Period (c. 1500–850 BC) along with other crops such as millet, wheat, and legumes.[15]

In the Pulitzer Prize-winning book Guns, Germs, and Steel, Jared Diamond argues that the availability of barley, along with other domesticable crops and animals, in southwestern Eurasia significantly contributed to the broad historical patterns that human history has followed over approximately the last 13,000 years; i.e., why Eurasian civilizations, as a whole, have survived and conquered others.[16]

Barley beer was probably the first drink developed by Neolithic humans.[17] Barley later on was used as currency.[17] Alongside emmer wheat, Barley was a staple cereal of ancient Egypt, where it was used to make bread and beer. The general name for barley is jt (hypothetically pronounced "eat"); šma (hypothetically pronounced "SHE-ma") refers to Upper Egyptian barley and is a symbol of Upper Egypt. The Sumerian term is akiti. According to Deuteronomy 8:8, barley is one of the "Seven Species" of crops that characterize the fertility of the Promised Land of Canaan, and barley has a prominent role in the Israelite sacrifices described in the Pentateuch (see e.g. Numbers 5:15). A religious importance extended into the Middle Ages in Europe, and saw barley's use in justice, via alphitomancy and the corsned.

Barley in Egyptian hieroglyphs
jt barley determinative/ideogram
jt (common) spelling
šma determinative/ideogram

In ancient Greece, the ritual significance of barley possibly dates back to the earliest stages of the Eleusinian Mysteries. The preparatory kykeon or mixed drink of the initiates, prepared from barley and herbs, referred in the Homeric hymn to Demeter, whose name some scholars believe meant "Barley-mother".[18] The practice was to dry the barley groats and roast them before preparing the porridge, according to Pliny the Elder's Natural History (xviii.72). This produces malt that soon ferments and becomes slightly alcoholic.

Pliny also noted barley was a special food of gladiators known as hordearii, "barley-eaters". However, by Roman times, he added that wheat had replaced barley as a staple.[19]

Tibetan barley has been a staple food in Tibet since the 5th century AD. This grain, along with a cool climate that permitted storage, produced a civilization that was able to raise great armies.[20] It is made into a flour product called tsampa that is still a staple in Tibet.[21] The flour is roasted and mixed with butter and butter tea to form a stiff dough that is eaten in small balls.

In medieval Europe, bread made from barley and rye was peasant food, while wheat products were consumed by the upper classes.[19] Potatoes largely replaced barley in Eastern Europe in the 19th century.[22]

Production

Top ten barley producers — 2009
(million metric tonne)
 Russia 17.9
 France 12.9
 Germany 12.3
 Ukraine 11.8
 Canada 9.5
 Australia 8.1
 Turkey 7.3
 United Kingdom 6.8
 United States 4.9
 Poland 4.0
World total 152
Source:
UN Food & Agriculture Organization (FAO)
[23]

Barley was grown in about 100 countries worldwide in 2007. The world production in 1974 was 148,818,870 tonnes; since then, there has been a slight decline in the amount of barley produced worldwide.[19]

Cultivation

Barley is a widely adaptable crop. It is currently popular in temperate areas where it is grown as a summer crop and tropical areas where it is sown as a winter crop. Its germination time is anywhere from 1 to 3 days. Barley likes to grow under cool conditions but is not particularly winter hardy.

Barley is more tolerant of soil salinity than wheat, which might explain the increase of barley cultivation in Mesopotamia from the 2nd millennium BC onwards. Barley is not as cold tolerant as the winter wheats (Triticum aestivum), fall rye (Secale cereale) or winter TriticaleTriticosecale Wittm. ex A. Camus.), but may be sown as a winter crop in warmer areas of the world such as Australia.

Barley has a short growing season and is also relatively drought tolerant.[19]

Plant diseases

This plant is known or likely to be susceptible to barley mild mosaic bymovirus[24][25] as well as bacterial blight. Barley can be susceptible to many diseases but plant breeders have been working hard to incorporate resistance. The devastation caused by any one disease will depend upon the susceptibility of the variety being grown and the environmental conditions during disease development. Serious diseases of barley include powdery mildew, caused by Blumeria graminis f.sp. hordei, Leaf Scald, caused by Rhynchosporium secalis, Barley rust, caused by Puccinia hordei, and various diseases caused by Cochliobolus sativus. Fusarium species cause Head Blight (Am. http://en.wikipedia.org/wiki/Fusarium_ear_blight)

Uses

Algicide

Barley straw, in England, is placed in mesh bags and floated in fish ponds or water gardens to help reduce algal growth without harming pond plants and animals. Barley straw has not been approved by the EPA for use as a pesticide and its effectiveness as an algicide in ponds has produced mixed results during university testing in the US and the UK.[26]

Animal feed

Half of the United States' barley production is used as an calf feed.[27] Barley is an important feed grain in many areas of the world not typically suited for maize production, especially in northern climates - for example, northern and eastern Europe. Barley is the principal feed grain in Canada, Europe, and in the northern United States.[28] A finishing diet of barley is one of the defining characteristics of Western Canadian beef used in marketing campaigns.[29]

Beverages

Alcoholic beverages

A large part of the remainder is used for malting, for which barley is the best suited grain.[30] It is a key ingredient in beer and whisky production. Two-row barley is traditionally used in German and English beers. Six-row barley was traditionally used in US beers, but both varieties are in common usage now.[31] Distilled from green beer,[32] whisky has been made primarily from barley in Ireland and Scotland, while other countries have utilized more diverse sources of alcohol; such as the more common corn, rye and wheat in the USA. In the USA, a grain type may be identified on a whisky label if that type of grain constitutes 51% or more of the ingredients and certain other conditions are satisfied.[33]

Barley wine was an alcoholic drink in the 18th century. It was prepared by boiling barley in water, then mixing the barley water with white wine and other ingredients like borage, lemon and sugar. In the 19th century a different barley wine was made prepared from recipes of ancient Greek origin.[3]

Non-alcoholic beverages

Non-alcoholic drinks such as barley water[3] and barley tea (called mugicha in Japan)[34] have been made by boiling barley in water.

Food

Raw barley
Nutritional value per 100 g (3.5 oz)
Energy 1,474 kJ (352 kcal)
Carbohydrates 77.7 g
- Sugars 0.8 g
- Dietary fiber 15.6 g
Fat 1.2 g
Protein 9.9 g
Thiamine (vit. B1) 0.2 mg (17%)
Riboflavin (vit. B2) 0.1 mg (8%)
Niacin (vit. B3) 4.6 mg (31%)
Pantothenic acid (B5) 0.3 mg (6%)
Vitamin B6 0.3 mg (23%)
Folate (vit. B9) 23 μg (6%)
Vitamin C 0.0 mg (0%)
Calcium 29.0 mg (3%)
Iron 2.5 mg (19%)
Magnesium 79.0 mg (22%)
Phosphorus 221 mg (32%)
Potassium 280 mg (6%)
Zinc 2.1 mg (22%)
Percentages are relative to US recommendations for adults.
Source: USDA Nutrient Database

Barley contains eight essential amino acids.[35][36] According to a recent study, eating whole grain barley can regulate blood sugar (i.e. reduce blood glucose response to a meal) for up to 10 hours after consumption compared to white or even whole-grain wheat, which has a similar glycemic index.[37] The effect was attributed to colonic fermentation of indigestible carbohydrates. Barley can also be used as a coffee substitute.

Hulled barley (or covered barley) is eaten after removing the inedible, fibrous outer hull. Once removed, it is called dehulled barley (or pot barley or scotch barley).[38] Considered a whole grain, dehulled barley still has its bran and germ making it a nutritious and popular health food. Pearl barley (or pearled barley) is dehulled barley which has been steam processed further to remove the bran.[38] It may be polished, a process known as "pearling". Dehulled or pearl barley may be processed into a variety of barley products, including flour, flakes similar to oatmeal, and grits.

Barley-meal, a wholemeal barley flour which is lighter than wheatmeal but darker in colour, is used in porridge and gruel in Scotland.[38] Barley-meal gruel is known as Sawiq in the Arab world.[39] With a long history of cultivation in the Middle East, barley is used in a wide range of traditional Assyrian, Arabic, Israelite, Kurdish, Persian, and Assyrian foodstuffs including kashkak, kashk and murri. Barley soup is traditionally eaten during Ramadan in Saudi Arabia.[40] Cholent or Hamin (in Hebrew) is a traditional Jewish stew often eaten on the Sabbath, in a variety of recipes by both Mizrachi and Ashkenazi Jews, with barley cited throughout the Hebrew Bible in multiple references. In Eastern Europe, barley is also used in soups and stews. In Africa, where it is a traditional food plant, it has the potential to improve nutrition, boost food security, foster rural development and support sustainable landcare.[41]

The six row variety bere is cultivated in Orkney, Shetland, Caithness and the Western Isles in the Scottish Highlands and islands. The grain is used to make beremeal, used locally in bread, biscuits, and the traditional beremeal bannock.[42]

Like wheat and rye, barley contains gluten which makes it an unsuitable grain for consumption by those with celiac disease.

Measurement

Barley grains were used for measurement in England, there being 3 or 4 barleycorns to the inch and 4 or 5 poppy seeds to the barleycorn.[43] The statute definition of an inch was 3 barleycorns, although by the 19th century this had been superseded by standard inch measures.[44] This unit still persists in the shoe sizes which are used in Britain and the USA.[45]

The barleycorn was known as arpa in Turkish, and the feudal system in Ottoman Empire employed the term Arpalik, or "barley-money", to refer to a second allowance made to officials to offset the costs of fodder for their horses.[46]

Ornamental

A new stabilized variegated variety of Hordeum vulgare, billed as Hordeum vulgare varigate, has been introduced for cultivation as an ornamental and pot plant for pet cats to nibble on.[47]

Research

The chlorophyll binding a/b protein is missing in albostrains of barley, and they have been used to study plastid development in plants. Researching white streaked strains, plant scientists have gained a greater understanding of reporter gene expression in the production of chloroplast proteins.[48]

Cultural significance

In Islam, Muhammad prescribed barley (Talbina) for seven diseases.[49] It was also said to soothe and calm the bowels. Avicenna in his 11th century work The Canon of Medicine wrote of the healing effects of barley water, soup and broth for fevers.[50] Additionally, barley can be roasted and turned into roasted barley tea, a popular Asian drink.

In English folklore, The figure of John Barleycorn in the folksong of the same name is a personification of barley, and of the alcoholic beverages made from it, beer and whisky. In the song, John Barleycorn is represented as suffering attacks, death, and indignities that correspond to the various stages of barley cultivation, such as reaping and malting. He may be related to older pagan gods such as Mímir or Kvasir.[51]

See also

References

Notes

  1. ^ "Hordeum vulgare". Integrated Taxonomic Information System. http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=40874. 
  2. ^ "FAOSTAT". Food and Agriculture Organization of the United Nations. http://faostat.fao.org/faostat. Retrieved 2009-05-18. 
  3. ^ a b c d Ayto, John (1990). The glutton's glossary : a dictionary of food and drink terms. London: Routledge. pp. 16–17. ISBN 0415026474. http://books.google.com/?id=vAQOAAAAQAAJ&pg=PA17&dq=barley+water+was+used 
  4. ^ J. Simpson, E. Weiner (eds), ed (1989). "barley". Oxford English Dictionary (2nd ed.). Oxford: Clarendon Press. ISBN 0-19-861186-2. 
  5. ^ "Dictionary of the Scots Language: "DSL - SND1 BEAR, BERE, Beer, Bar"". http://www.dsl.ac.uk/dsl/getent4.php?plen=18327&startset=1964317&query=BEAR&fhit=bere&dregion=form&dtext=snd#fhit. Retrieved 2008-11-19. 
  6. ^ Smout, T.C. (1972) A History of the Scottish People 1560-1830 p114
  7. ^ "Dictionary of the Scots Language: "DSL - DOST Bere, Beir"". http://www.dsl.ac.uk/dsl/getent4.php?plen=6222&startset=3242554&query=Bere&fhit=bere&dregion=form&dtext=dost#fhit. Retrieved 2008-11-19. 
  8. ^ a b c d e f g Zohary, Daniel; Maria Hopf (2000). Domestication of Plants in the Old World: The Origin and Spread of Cultivated Plants in West Asia, Europe, and the Nile Valley (3rd ed.). Oxford University Press. pp. 59–69. ISBN 0198503571. http://books.google.com/?id=C1H6_XWJS_gC&pg=PA59&vq=barley&dq=Domestication+of+Plants+in+the+Old+World:+The+Origin+and+Spread+of+Cultivated+Plants+in+West+Asia,+Europe,+and+the+Nile+Valley. 
  9. ^ Komatsuda, T.; Pourkheirandish, M; He, C; Azhaguvel, P; Kanamori, H; Perovic, D; Stein, N; Graner, A et al. (2006). "Six-rowed barley originated from a mutation in a homeodomain-leucine zipper I-class homeobox gene". Proceedings of the National Academy of Sciences of the United States of America 104 (4): 1424–1429. doi:10.1073/pnas.0608580104. PMC 1783110. PMID 17220272. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1783110. 
  10. ^ Adrian Johnston, Scott Murrell, and Cynthia Grant. "Nitrogen Fertilizer Management of Malting Barley: Impacts of Crop and Fertilizer Nitrogen Prices (Prairie Provinces and Northern Great Plains States)". International Plant Nutrition Institute. http://www.ppi-far.org/ppiweb/ppibase.nsf/$webindex/article=0EA04C0385256CF50062045A0D8E2931. Retrieved 2009-05-28. 
  11. ^ Bhatty, R.S. (1999). "The potential of hull-less barley". Cereal Chemistry 76 (5): 589–599. doi:10.1094/CCHEM.1999.76.5.589. 
  12. ^ Bhatty, R.S. (2011). "β-glucan and flour yield of hull-less barley". Cereal Chemistry 76 (2): 314–315. doi:10.1094/CCHEM.1999.76.2.314. 
  13. ^ NSLC.wustl.edu
  14. ^ -Saltini Antonio, I semi della civiltà. Grano, riso e mais nella storia delle società umane,, prefazione di Luigi Bernabò Brea Avenue Media, Bologna 1996
  15. ^ Crawford, Gary W.; Gyoung-Ah Lee (2003). "Agricultural Origins in the Korean Peninsula". Antiquity 77 (295): 87–95. ISSN 0003-598X. 
  16. ^ Diamond, Jared M. (1997). Guns, germs, and steel: the fates of human societies. New York: W.W. Norton. pp. 141. ISBN 0-393-03891-2. 
  17. ^ a b Pellechia, Thomas (2006). Wine : the 8,000-year-old story of the wine trade. Philadelphia: Running Press. pp. 10. ISBN 1560258713. http://books.google.com/?id=K6OTKiIlyAIC&pg=PA10&dq=barley+beer+first+drink 
  18. ^ J. Dobraszczyk, Bogdan (2001). Cereals and cereal products: chemistry and technology. Gaithersburg, Md.: Aspen Publishers. pp. 7. ISBN 0-8342-1767-8. 
  19. ^ a b c d McGee, p. 235
  20. ^ Fernandez, Felipe Armesto (2001). Civilizations: Culture, Ambition and the Transformation of Nature. pp. 265. ISBN 0743216504 
  21. ^ Dreyer, June Teufel; Sautman, Barry (2006). Contemporary Tibet : politics, development, and society in a disputed region. Armonk, New York: Sharpe. pp. 262. ISBN 0765613549. http://books.google.com/?id=Ou4f4q8gGcIC&pg=PA262&dq=tsampa, 
  22. ^ Roden, Claudia (1997). The Book of Jewish Food. Knopf. pp. 135. ISBN 0394532589. 
  23. ^ FAOSTAT.fao.org
  24. ^ Brunt, A. A., Crabtree, K., Dallwitz, M. J., Gibbs, A. J., Watson, L. and Zurcher, E. J. (editors) (20 August 1996). "Plant Viruses Online: Descriptions and Lists from the VIDE Database". http://image.fs.uidaho.edu/vide/refs.htm. 
  25. ^ "Barley mild mosaic bymovirus". http://image.fs.uidaho.edu/vide/descr059.htm. 
  26. ^ BTNY.edu
  27. ^ "Barley". http://www.hort.purdue.edu/newcrop/Crops/Barley.html. Retrieved 2008-02-02. 
  28. ^ AG.ndsu.edu
  29. ^ OMAFRA.gov.on.ca
  30. ^ McGee, p. 471
  31. ^ Ogle, Maureen (2006). Ambitious brew : the story of American beer. Orlando: Harcourt. pp. 70–72. ISBN 0151010129. http://books.google.com/?id=0vuOyazwh4YC&pg=PA71&dq=and+six-row+barley+was+traditionally+used+in+US+beers. 
  32. ^ McGee, p. 481
  33. ^ McGee, p. 490
  34. ^ Clarke, ed by R J (1988). Coffee. London: Elsevier Applied Science. pp. 84. ISBN 1851661034. http://books.google.com/?id=n9ZEMquvPoYC&pg=PA84&dq=mugicha 
  35. ^ Womens-health-symmetry.com
  36. ^ Essentialfood.co.uk
  37. ^ Nilsson, A.; et al. (2006). "Effects of GI and content of indigestible carbohydrates of cereal-based evening meals on glucose tolerance at a subsequent standardised breakfast". European Journal of Clinical Nutrition 60 (9): 1092–1099. doi:10.1038/sj.ejcn.1602423. PMID 16523203. 
  38. ^ a b c Simon, André (1963) Guide to Good Food and Wines: A Concise Encyclopedia of Gastronomy Complete and Unabridged p. 150 Collins, London
  39. ^ Tabari, W. Montgomery Watt, M. V. McDonald (1987). The History of Al-Tabari: The Foundation of the Community: Muhammad at Al-Madina, A. D. 622-626/ijrah-4 A. H.. SUNY Press. ISBN 0887063446, 9780887063442. http://books.google.com/?id=ctvk-fdtklYC&pg=PA89&dq=barley+sawiq. 
  40. ^ Long, David E. (2005). Culture and customs of Saudi Arabia. Greenwood Publishing Group. pp. 50. ISBN 0313320217. 
  41. ^ National Research Council (1996-02-14). "Other Cultivated Grains". Lost Crops of Africa: Volume I: Grains. Lost Crops of Africa. 1. National Academies Press. pp. 243. ISBN 978-0-309-04990-0. http://books.nap.edu/openbook.php?record_id=2305&page=237. Retrieved 2008-07-25. 
  42. ^ Martin, Peter; Xianmin Chang (2008-06). "Bere Whisky: rediscovering the spirit of an old barley". The Brewer & Distiller International 4 (6): 41–43. http://www.ibd.org.uk. Retrieved 2008-11-14. 
  43. ^ Oxford English Dictionary. Oxford University Press. 2009. http://dictionary.oed.com 
  44. ^ George Long (1842). The Penny Cyclopædia of the Society for the Diffusion of Useful Knowledge. C. Knight. p. 436. http://books.google.com/?id=rJhOFg1yiqUC 
  45. ^ Cairns, Warwick (2007). About the Size of It. Macmillan. ISBN 978-0-230-01628-6. 
  46. ^ Houtsma M Th; Arnold TW, Wensinck AJ (1993). E.J. Brill's First Encyclopaedia of Islam, 1913-1936. Brill. pp. 460. ISBN 9004097961. 
  47. ^ www.loghouseplants.com/images/catgrass2.pdf
  48. ^ Jaiswal, Vijai Shanker; Ram, V. S. Jaiswal H. Y. Mohan (2000). The Changing Scenario in Plant Sciences. Allied Publishers Pvt. Ltd.. pp. 299. ISBN 81-7764-021-6. http://books.google.com/?id=AjU2O0JrF3IC&pg=PA299. 
  49. ^ Hadith. Volume 7, Book 71, Number 593: (Narrated 'Ursa)
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Bibliography

External links