APA

Hoffman G. J., Evans R. G. & Jensen M. E.Design and operation of farm irrigation system. United States of America:American Society of Agricultural and Biological Engineers, 2007: .

Chicago

Hoffman Glenn J, Evans Robert G and Jensen Marvin E.Design and operation of farm irrigation system. United States of America:American Society of Agricultural and Biological Engineers, 2007: .

Harvard

Hoffman G. J., Evans R. G. and Jensen M. E.Design and operation of farm irrigation system. United States of America:American Society of Agricultural and Biological Engineers, 2007: .

MLA

Hoffman Glenn J, Evans Robert G and Jensen Marvin E.United States of America:American Society of Agricultural and Biological Engineers, 2007: . .