Bear, R.S., X-Ray Diffraction Studies on Protein Fibers. II: Feather Rachis, Porcupine Quill Tip and Clam Muscle, J. Amer. Chem. Soc . 66, 2043-2050 (1944).
2.
Fraser, R.D.B. , and MacRae, T.P., Evidence of Regularities in the Chemical Structure of α-Keratin, Nature179, 732-733 (1957).
3.
Fraser, R.D.B. and MacRae, T.P., Structure of α-Keratin, Nature233, 138-140 (1971).
4.
Lang, A.R., An X-Ray Study of α-Keratin. II: Diffractometer Measurements of the Complete Diffraction Pattern of Canadian Porcupine Quill, Acla Cryst. 9, 446-451 (1956).
5.
MacArthur, I., Structure of α-Keratin, Nature. 152, 38-41 (1943).