1. C. J. Blankley, J. C. Hodges, J. S. Kiely and S. Klutchko, U. S. Patent 4,812,462 (1989).
2. Identification of angiotensin II receptor subtypes
3. P. R. Bovy and E. H. Blaine, Current Patents Ltd., 2044 (1989).
4. Y Furukawa, S. Kishimoto and K. Nishikawa, Takada Chemical Industries Ltd. U. S. Patent 4,355,040 (1982).