@book{54506, author = {Casley, D. J. and Lury, D. A.}, title = {Data collection in developing countries /}, publisher = {Clarendon Press ;}, year = {1987.}, address = {Oxford :}, edition = {2nd ed.}, url = {http://www.loc.gov/catdir/enhancements/fy0638/87012574-d.html} }