1. (1) Y. Ikada, et al.: Fundamentals and Applications of Biodegradable Polymers, Industrial Publishing & Consulting, Inc., Tokyo (1999) (in Japanese)
2. (2) N. Shiraishi, Y. Tani, K. Kudo, and K. Fukuda : Biodegradable Plastics, advances in it's practical application, Kogyo Chosakai Publishing Co., Ltd., Tokyo (2000) (in Japanese)
3. (3) Y. Inoue, et al.: Recent Advances in Research and Development for Green Plastics, CMC Publishing Co., Ltd., Tokyo (2002) (in Japanese)
4. (4) H. Tsuji: Biodegradable Polymers, Corona Publishing Co., Ltd., Tokyo (2002) (in Japanese)
5. (5) Biodegradable Plastics Society (BPS): http://www.bpsweb.net/02_english/index.htm