Rodriguez-Salas N, Dominguez G, Barderas R, Mendiola M, Garcia-Albeniz X, Maurel J, Batlle JF. Clinical relevance of colorectal cancer molecular subtypes. Crit Rev Oncol Hematol. 2017 Jan;109:9-19. doi: 10.1016/j.critrevonc.2016.11.007
Rothman KJ, Velez H, Glass RL, Mejia R, Espinal F. Dental caries and soil contents of trace metals in two Colombian villages. J Dent Res. 1972 Nov 1;51(6):1686.