Não informado. (1981). Soil and tillage research. Elsevier Scientific.
Lua i Stíl Chicago (17ú heag.)Não informado. Soil and Tillage Research. Amsterdam: Elsevier Scientific, 1981.
Lua MLA (8ú heag.)Não informado. Soil and Tillage Research. Elsevier Scientific, 1981.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.