Moldin, S. O., Rice, J. P., Gottesman, I. I., & Erlenmeyer-Kimling, L. (1990). Psychometric deviance in offspring at risk for schizophrenia: II. Resolving heterogeneity through admixture analysis. Psychiatry Research, 32(3), 311–322. http://www.elsevier.com/inca/publications/store/5/2/2/7/7/3/