1. Defrise, E.: 1955, Mesure de divergence Λ2 entre un sujet déterminé et une population multivariée normale. Bulletin Institut Royal des Sciences Naturelles de Belgique, 31, 1–15.
2. Defrise, E.: 1967, Generalized distance in genetic studies. Acta Genetica, 17, 275–288.
3. Defrise, E.: 1968, Non-central chi-square in twin studies. Acta Genetica, l8, 170–179.
4. Defrise, E.: 1970, Multivariate analysis in twins. Acta Geneticae Medicae et Gemellologiae, 19, 150–154.
5. Eaves, L.J., Martin, N.G., and Eysenck, S.B.: 1977, An application of the analysis of covariance structures to the psychogenetical study of impulsiveness. Brit. J. Mathem Stat. Psych, 30, 185.