Data originally from pages 357-360 of Andrews, D. F., and A. M. Herzberg. 1985. Data: A Collection of Problems from Many Fields for the Student and Research Worker. New York: Springer.
Source: Data taken from example 6.1.7, Table 6.2. Rootstock data, 170-173, of Rencher, A. C. 2002. Methods of Multivariate Analysis. 2nd ed. New York: Wiley.