1. Larson, L. L. 1974. High cost of low reproduction. Nebraska Dairy Report EC 74-220:10.
2. Nicolai, J. H., Jr., and L. C. Ulberg. 1967. North Carolina's system of herd reproductive status. Paper presented at the 20th Annu. Convention Nat. Ass. Anim. Breeders, September 7. Hershey, PA.
3. Pelissier, C. L. 1970. Factors contributing to low breeding efficiency in dairy herds. Mimeograph with paper E2 presented at the Sixty-fifth ADSA Annual Meeting, Gainesville, FL.