Saigi N, Espelt A, Folch C, Sarasa-Renedo A, Castellano Y, Majo X, Merono M, Brugal MT, Casabona J, REDAN Group. Differences in illegal drug consumption between native and immigrants in a large sample of injected drug users in Catalonia (Spain). Adicciones. 2014;26(1):69-76. doi: 10.20882/adicciones.136
Glass RL, Rothman KJ, Espinal F, Velez H, Smith NJ. Prevalence of human dental caries and water-borne trace metals. Arch Oral Biol. 1973 Sep;18(9):1099-104. doi: 10.1016/0003-9969(73)90083-6