Yoshimura, Yuichi; Kitano, Kenji; Watanabe, Mikari; Satoh, Hiroshi; Sakata, Shinji; Miura, Shinji; Ashida, Noriyuki; Machida, Haruhiko; Matsuda, Akira Nucleosides and Nucleotides, 1997, vol. 16, # 7-9 p. 1103 - 1106