Sharp L, Donnelly D, Hegarty A, Carsin AE, Deady S, McCluskey N, Gavin A, Comber H. Risk of several cancers is higher in urban areas after adjusting for socioeconomic status. Results from a two-country population-based study of 18 common cancers. J Urban Health. 2014 Jun;91(3):510-25. doi: 10.1007/s11524-013-9846-3
Williams RE, Bosnic N, Sweeney CT, Duncan AW, Levine KB, Brogan M, Cook SF. Prevalence of opioid dispensings and concurrent gastrointestinal medications in Quebec. Pain Res Manag. 2008;13(5):395-400.