1. E. H. Mercer. “The Electron Microscopy of Keratinized Tissues”, in “The Biology of Hair Growth” Ed. H. Montagna and R. A. Ellis, Acad. Press Inc., 1958, 91.
2. F. O. Schmitt.Growth, 1941, 5, suppl. 1.
3. H. G. Howell. “The Friction of Wool” in “Friction in Textiles”, by H. G. Howell, K. W. Mieszkis and D. Tabor. Butterworths Scientific Publ., 1959, 79.
4. J. L. Stoves. “Fibre Microscopy”, National Trade Press, 1957.
5. P. Kassenbeck. Première Semaine Internationale de la Technique Textile, Barcelona, 1959.