1. R. D. Knutson, V. K. Johnson, C. N. Haugse, and M. L. Buchanan : 1966 , 'Variation in Tenderness of Beef Muscle',North Dakota State Ag. Exp. Station Tech. Bull., p.464.
2. H. W. Schultz : 1957 , 'Mechanical Methods of Measuring Tenderness of Meat', Proceedings Tenth Annual Reciprocal Meat Conference.