Behrend; Roosen Justus Liebigs Annalen der Chemie, 1889 , vol. 251, p. 238 Full Text Show Details Biltz; Paetzold Justus Liebigs Annalen der Chemie, 1927 , vol. 452, p. 79 Full Text Show Details Levene Journal of Biological Chemistry, 1925 , vol. 63, p. 658