1. The inhibitory effect of fentanyl and other morphine like analgesics on the warm water induced tail withdrawal reflex in rats;Janssen;Arznei.-Forschung,1963
2. Sufentanil, a very potent and extremely safe intravenous morphine-like compound in mice, rats and dogs;Niemegeers;Arznei.-Forschung,1976
3. Alfentainil (R 39209) a particularly short acting intravenous narcotic analgesic in rats;Niemegeers;Drug Dev. Res.,1981
4. Synthetic 1,4-disubstituted-1,4-dihydro-5H-tetrazol-5-one derivatives of fentanyl: alfentanil (R 39209), a potent, extremely short-acting narcotic analgesic;Janssens;J. Med. Chem.,1986
5. Comparison between epidural fentanyl, sufentanil, carfentanil, lofentanil and alfentanil in the rat: analgesia and other in vivo effects;Meert;Eur. J. Anaesth.,1988