Buschmann H., Christoph T., Friderichs E., Maul C., Sundermann B. Analgesics from Chemistry and Pharmacology to Clinical Application. - 2002. - pp. 219
Clarke's isolation and identification of drugs. - 2ed. - London: Pharmaceutical press, 1986. - pp. 867
Kleemann A. Pharmaceutical Substances. - 2000. - pp. 1603-1604
Problems of Drug Dependence 1991: Proceeding of the 53rd Annual Scientific Meeting The Committee on Problems of Drug Dependence, 1992. - pp. 519
Химико-фармацевтический журнал. - 1991. - №7. - pp. 22 [Russian]