Simoes Eduardo J, Sumaya Ciro V
National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, 4770 Buford Hwy, NE, MS K-45, Atlanta, GA 30341, USA.
J Prim Prev. 2010 Apr;31(1-2):21-9. doi: 10.1007/s10935-010-0201-0.