1. K. Imada, M. Takayanagi, and T. Yamamoto, a paper presented at the 18th Annual Meeting of the Society of Polymer Science, Japan (May 1969, Tokyo).
2. K. Imada, T. Yamamoto, K. Ueno, D. Matsukuma, and M. Takayanagi, J. Soc. Mater. Sci. Japan 19 (1970) 302.
3. Idem, and M. Takayanagi, Rep. Prog. Polymer Phys. Japan 19 in press (1970). 302
4. A. Buckley and H. A. Long, Polymer Eng. Sci. 9 (1969) 115.
5. V. E. Malpass, Appl. Polymer Symposia 12 (1969) 19.