1. Akiyama Y., Miyao K.,(Akiyama Jozai KK) (1977): Jpn.Kokai, 77,114,060, (C.A. 88: 27825)
2. Ajinomoto Co. (1984): Jpn.Kokai 84,166,057,(C.A. 102: 23208)
3. Akiyama Y. (1979): Jpn.Kokai 79,80,463,(C.A. 92: 28556)
4. Arakawa K.(1974): Ger. Offen. 2,527,234,
5. Asaha Denka Kogyo K.K. (1980): Jpn.Kokai 80,87,701, (C.A. 93: 148524)