1. Collagen Determination, Comparison of Enzyme and Waring Blendor Methods for Determination of Collagen in Beef
2. American Meat Institute Foundation., 1960 . "The Science of Meat and Meat Products " p.216 . W. H. Freeman and Co., San FranciscoandLondon.
3. N. R. Frohberg, 1963 . Effect of age on collagen, elastin and mucoprotein content of chicken muscles . M.S. thesis , Iowa State University of Science and Technology, Ames, Iowa.