1. Butz RF, Jones EC, Welch RM, Findlay JWA (1983) Pharmacokinetics and O-dealkylation of morphine-3-alkyl ethers in the rat. Drug Metab Dispos 11:481–488
2. Cahen R (1961) The pharmacology of pholcodine. Bull Narc 13:19–36
3. Chabrier P, Giudicelli R, Thullier J (1950) Étude chimique, pharmacologique et clinique d'un nouveau sédative de la toux: la morpholinoéthylmorphine. Ann Pharm Fr 8:261–273
4. Eddy NB, Friebel H, Hahn KJ, Halbach H (1970) Codeine, and its alternatives for pain and cough relief. Bull WHO 40:160–164
5. Findlay JWA (1988) Review: pholcodine. J Clin Pharm Ther 13:5–17