Lin, ., Nan, ., Hingson, R., & Allwood-Paredes, J. (1971). Mass Immunization Campaign in El Salvador, 1969. HSMHA Health Reports, 86, 1112–1121.

Lin, Daniel, Daniel Nan, Ralph Hingson, and Juan Allwood-Paredes. “Mass Immunization Campaign in El Salvador, 1969.” HSMHA Health Reports 86 (1971): 1112–21.

Lin, Nan, Hingson R, Allwood-Paredes J. Mass Immunization Campaign in El Salvador, 1969. HSMHA Health Reports. 1971;86:1112–21.

Lin, Daniel, et al. “Mass Immunization Campaign in El Salvador, 1969.” HSMHA Health Reports, vol. 86, Reprinted in: Ekistics: Reviews of the Problems and Science of Human Settlements September 1972, 34(202), 1971, pp. 1112–21.

Lin, Nan, Hingson R, Allwood-Paredes J. Mass Immunization Campaign in El Salvador, 1969. HSMHA Health Reports. Reprinted in: Ekistics: Reviews of the Problems and Science of Human Settlements September 1972, 34(202); 1971;86:1112–1121.