Collegamenti
[1] https://www.burlo.trieste.it/ricerca/pubblicazioni/doing-without-codeine-why-and-what-are-alternatives
[2] https://www.burlo.trieste.it/ricerca/biblio?f%5Bauthor%5D=2596
[3] https://www.burlo.trieste.it/ricerca/biblio?f%5Bauthor%5D=2401
[4] http://www.ncbi.nlm.nih.gov/pubmed/24517264?dopt=Abstract