APA

Sheaffer C. C., Barnes D. K. & Heichel G. H. (1989). Annual Alfalfa in Crop Rotations. : .

Chicago

Sheaffer Craig C, Barnes Donald K and Heichel Gary H. 1989. Annual Alfalfa in Crop Rotations. : .

Harvard

Sheaffer C. C., Barnes D. K. and Heichel G. H. (1989). Annual Alfalfa in Crop Rotations. : .

MLA

Sheaffer Craig C, Barnes Donald K and Heichel Gary H. Annual Alfalfa in Crop Rotations. : . 1989.