1. GALE, J, ANNUAL REVIEW OF PLANT PHYSIOLOGY 17: 269 (1966).
2. LEBOVITS, A, MODERN PLASTICS 43: 139 (1966).
3. MICHIGAN STATE UNIVERSITY AGRICULTURAL EXPERIMENT STATION TECHNICAL BULLETIN 1950 218
4. Raff, R. A. V., High Polymers XI: 267 (1956).
5. Stannett, V., Crystalline Olefin Polymers: 131 (1964).