@BOOK {PLEYSIER:1991,
title = {Echantillonnage du sol et preparation des echantillons: Guide de recherche de I'iita, No. 2},
author = {Pleysier, J. L. },
series = {Guide de recherche de I'iita, No. 2},
year = {1991},
publisher = {International Institute of Tropical Agriculture (IITA)},
address = {Ibadan, Nigeria},
note = {26p.},
}