@BOOK {COUPER:1995,
title = {Building and maintenance of roads on agricultural research farms: IITA research guide, No. 20},
author = {Couper, D. C. },
series = {IITA research guide, No. 20},
year = {1995},
month = {September},
publisher = {International Institute of Tropical Agriculture (IITA)},
address = {Ibadan, Nigeria},
note = {20p.},
}