APA-referens (7:e uppl.)
Hellin, J. (2006). Better land husbandry: From soil conservation to holistic land management. Science Publishers.
Chicago-referens (17:e uppl.)
Hellin, Jon. Better Land Husbandry: From Soil Conservation to Holistic Land Management. Enfield, NH: Science Publishers, 2006.
MLA-referens (9:e uppl.)
Hellin, Jon. Better Land Husbandry: From Soil Conservation to Holistic Land Management. Science Publishers, 2006.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.