参考文献:
BRISTOL-MYERS SQUIBB COMPANY PRACITTO, Richard KADOW, John, F. BENDER, John, A. BENO, Brett, R. GRANT-YOUNG, Katharine HAN, Ying HEWAWASAM, Piyasena NICKEL, Andrew PARCELLA, Kyle, E. YEUNG, Kap-Sun CHUPAK, Louis, S. Patent: WO/86 A, Location in patent: Page/Page column 5-5 88-89 WO /86 A