Imamoto, Tsuneo; Hatajima, Toshihiko; Takiyama, Nobuyuki; Takeyama, Toshiaki; Kamiya, Yasuo; Yoshizawa, Takeshi Journal of the Chemical Society, Perkin Transactions 1: Organic and Bio-Organic Chemistry (1972-1999), 1991 , # 12 p. 3127 - 3135