Burgkart, M., Maucic, D. and Ritter, H. C. 1963. [A method for determining the speed of ultrasound waves in living cattle muscle.] Bayr Landwirtsch. 40: 567–571.
Dumont, B. L. 1959. [Measurement of the fatness of pigs by ultrasonic echoes.] C.r. hebd. Seanc. Acad. Agric. Fr. 45: 628–631.
Greenspan, M. and Tschiegg, C. E. 1959. Tables of the speed of sound in water. J. acoust. Soc. Am. 31: 75–76.
Krautkrämer, J. and Krautkramer, H. 1969. Ultrasonic Testing of Materials. Chap. 2. Springer-Verlag, New York.
Ludwig, G. D. 1950. The velocity of sound through tissues and the acoustic impedance of tissues. J. acoust. Soc. Am. 22: 862–866.
Miles, C. A., Pomeroy, R. W. and Harries, J. M. 1972. Some factors affecting reproducibility in ultrasonic scanning of animals. 1. Cattle. Anim. Prod. 15: 239–249.
Wells, P. N. T. 1969. Physical Principles of Ultrasonic Diagnosis. Chap. 1. Academic Press, London.