Pieri, C. J. M. G. (1992). Fertility of soils: A future for farming in the West African savannah. Springer-Verlag.
Lua i Stíl Chicago (17ú heag.)Pieri, Christian J. M. G. Fertility of Soils: A Future for Farming in the West African Savannah. Berlin: Springer-Verlag, 1992.
Lua MLA (9ú heag.)Pieri, Christian J. M. G. Fertility of Soils: A Future for Farming in the West African Savannah. Springer-Verlag, 1992.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.