Biblio

K. Wehrle, Pfiffner, H., Meuli, C., and Muller, H., Building construction, vol. no. 3. St. Gallen, Switzerland: SKAT (Swiss Centre for Development Cooperation in Technology and Management), 2000, p. 57 p. : fig., photogr., techn.drwg.

H. Pfiffner, “Summary of the gravity water supply design and hydraulic correspondence course”. Sarvodaya Rural Technical Services, Moratuwa, Sri Lanka, p. 47 p.: fig., 1989.