UNICEF - New York, US, “The impact of manual drilling for the construction of sustainable water-points in Chad : case study”. Practica Foundation, Papendrecht, The Netherlands, p. 12 p.; 1 box; 1 fig.; 4 photographs, 2009.

UNICEF - New York, US, “Sustainable transfer of manual well dril[l]ing to the private sector in Niger : case study”. Practica Foundation, Papendrecht, The Netherlands, p. 8 p.; 1 box; 1 fig.; 7 photographs; 2 tab., 2009.