APA-viite

Giller,Ken E, & wilson,kate j. (1991). Nitrogen fixation in tropical croping systems. CAB international.

Chicago-tyylinen lähdeviittaus

Giller,Ken E, ja wilson,kate j. Nitrogen Fixation in Tropical Croping Systems. United Kingdom: CAB international, 1991.

MLA-viite

Giller,Ken E, ja wilson,kate j. Nitrogen Fixation in Tropical Croping Systems. CAB international, 1991.