APA (7e ed.) Bronvermelding

Collings, G. H. (2002). Commercial fertilizers: Their sources and use (4th ed.). Biotech Books.

Chicago (17e ed.) Bronvermelding

Collings, Gilbeart H. Commercial Fertilizers: Their Sources and Use. 4th ed. Delhi: Biotech Books, 2002.

MLA (9e ed.) Bronvermelding

Collings, Gilbeart H. Commercial Fertilizers: Their Sources and Use. 4th ed. Biotech Books, 2002.