Macy, L. K., Arnold, L. E., McKibben, E. G., & Stone, E. J. (1937). Changes in technology and labor requirements in crop production: Sugar beets. s.n.
Chicago-viite (17. p.)Macy, Loring K., Lloyd E. Arnold, Eugene George McKibben, ja Edmund Jefferson Stone. Changes in Technology and Labor Requirements in Crop Production: Sugar Beets. Philadelphia, Pa: s.n, 1937.
MLA-viite (9. p.)Macy, Loring K., et al. Changes in Technology and Labor Requirements in Crop Production: Sugar Beets. s.n, 1937.
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.