1. S. Bergstrom, S. Bergstrom, and B. Samuelsson (1967 ): Nobel Symposium 2, Prostaglandins , Almqvist and Wiksell, Stockholm, p.21 .
2. Isolation of Prostaglandin E1 from Human Seminal Plasma
3. M. Bygdeman, S. Bergstrom, and B. Samuelsson (1967 ): Nobel Symposium 2, Prostaglandins . Almqvist and Wiksell, Stockholm, p.71 .