Varrassi G., Marinangeli F., Piroli A., Coaccioli S., Paladini A. (2010). Strong analgesics: working towards an optimal balance between efficacy and side effects. EUROPEAN JOURNAL OF PAIN, vol. 14(4), p. 340-342, ISSN: 1090-3801, doi: 10.1016/j.ejpain.2010.02.006
