Incidence, duration and determinants of cervical human papillomavirus infection in a cohort of Colombian women with normal cytology results. - Muñoz,N.; Mendez,F.; Posso,H.; Molano,M.; van den Brule,A.J.; Ronderos,M.; Meijer,C.MJ.; Muñoz,A. (J Infect Dis, 2004)