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2. “The Physiology of Domestic Animals,” Ed. 4;Dukes,1937
3. Espe, D.L. 1938. Personal Communication.
4. Experiments in feeding cows and calves;Hooper;Ky. Agric. Expt. Sta. Bull.,1913
5. Quoted by Morris S. in Biennial reviews of the progress of dairy science;Lankeit;J. Dairy Res.,1937