Gustafson, A. (1997). Hand book of fertilizers: Their sources, makeup, effects and use. ABP.
Cita Chicago (17th ed.)Gustafson, A.F. Hand Book of Fertilizers: Their Sources, Makeup, Effects and Use. New Delhi: ABP, 1997.
Cita MLA (9th ed.)Gustafson, A.F. Hand Book of Fertilizers: Their Sources, Makeup, Effects and Use. ABP, 1997.
Atenció: Aquestes cites poden no estar 100% correctes.