1. Brandt, A. E. 1943. Tests of significance in reversal or switch back trials. Page 61 in Iowa Agric. Exp. Stn. Res. Bull. 234.
2. Multiple range and multiple F Tests;Duncan,1953
3. SAS Users guide;Helwig,1979
4. Milk production, health and endocrine responses of cows exposed to electrical current during milking;Henke Drenkard;J. Dairy Sci.,1984
5. Sensitivity of cows to transient electrical current;Henke Drenkard;J. Dairy Sci.,1982