G. F. Craun, Calderon, R. L., and Frost, F. J.,
“An introduction to epidemiology”,
Journal American Water Works Association, pp. p. 54-65 : 1 fig., 11 tab., ill., 1996.
G. F. Craun, Calderon, R. L., and Frost, F. J.,
“Waterborne disease surveillance”,
Journal American Water Works Association, pp. p. 66-75 : 4 boxes, 2 fig., 1 tab., 1996.
