Rural Water Supply – Constructing Structures for Springs, Technical Note No. RWS. 1.C.1.

WFTW (1982): Rural Water Supply – Constructing Structures for Springs, Technical Note No. RWS. 1.C.1.. Washington D.C. (USA): Water for the World (WFTW), U.S. Agency for International Development URL [Accessed: 01.09.2018] PDF