M. Snel, Ganguly, S., y Shordt, K.,
School sanitation and hygiene education - India. Handbook for teachers, vol. no. 39. Delft, The Netherlands: IRC, 2002, p. 45 p. : boxes, fig., tab.
M. Snel, Ganguly, S., y Shordt, K.,
School sanitation and hygiene education - India. Resource book, vol. no. 39. Delft, The Netherlands: IRC, 2002, p. 268 p. : boxes, fig., tab.