1Canh D G, Whittington D, Thoa L T K. Household demand for typhoid fever vaccines in Hue, Vietnam[J]. Health policy and planning, 2006,21 (3) :241 -255.
2L H, H D, M F, et al. Experience with Salmonella typhi Vi capsular polysaccharide vaccine[J]. European Journal of Clinical Microbiology and Infectious Diseases, 1999,18:609 - 620.