Gaya APA

AZEVEDO, L, F. et al (2013). A Population-based study On Chronic Pain and The Use Of Opioids In Portugal . Washington: IASP.

Gaya MLA

AZEVEDO, Luis, Filipe. et al. "A Population-based study On Chronic Pain and The Use Of Opioids In Portugal". Washington: IASP, 2013. Artikel.