1. The Merck Index & Co. Inc., Whitehouse Station, NJ, USA, 3737, 2001.
2. M. Zając, E. Pawełczyk, Chemia Leków, AM Poznań (2000) 188.
3. The Merck Index & Co. Inc., Whitehouse Station, NJ, USA, 320, 2001.
4. The Merck Index & Co. Inc., Whitehouse Station, NJ, USA, 8324, 2001.
5. Annales UMCS;Modzelewska,1995