Anatomical Data from Domestic Cats
The heart and body weights of samples of male and female cats used for digitalis experiments. The cats were all adult, over 2 kg body weight.
R. A. Fisher (1947) The analysis of covariance method for the relation between a part and the whole, Biometrics 3, 65--68.
Venables, W. N. and Ripley, B. D. (2002) Modern Applied Statistics with S. Fourth edition. Springer.