APA (7th ed.) Citation

Gregory, R. H., & Van Horn, R. L. (1960). Automatic data-processing systems: Principles and procedures / R. H. Gregory [and] Richard L. Van Horn. Wadsworth.

Chicago Style (17th ed.) Citation

Gregory, Robert Henry, and Richard L. Van Horn. Automatic Data-processing Systems: Principles and Procedures / R. H. Gregory [and] Richard L. Van Horn. Belmont, Calif: Wadsworth, 1960.

MLA (9th ed.) Citation

Gregory, Robert Henry, and Richard L. Van Horn. Automatic Data-processing Systems: Principles and Procedures / R. H. Gregory [and] Richard L. Van Horn. Wadsworth, 1960.