Giller, K. E. (1993). Nitrogen fixation in tropical cropping: Systems. C.A.B,I.
Cita Chicago (17th ed.)Giller, Ken E. Nitrogen Fixation in Tropical Cropping: Systems. Wallingford: C.A.B,I, 1993.
Cita MLA (9th ed.)Giller, Ken E. Nitrogen Fixation in Tropical Cropping: Systems. C.A.B,I, 1993.
Atenció: Aquestes cites poden no estar 100% correctes.