Hatfield, J. (1994). Soil biology: Effects on soil quality. Lewis Publishers.
Lua i Stíl Chicago (17ú heag.)Hatfield, J.L. Soil Biology: Effects on Soil Quality. Boca Raton: Lewis Publishers, 1994.
Lua MLA (9ú heag.)Hatfield, J.L. Soil Biology: Effects on Soil Quality. Lewis Publishers, 1994.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.