1. Measures of twin concordance;Allen;Acta Genet.,1967
2. Twin studies of affective illness;Allen;Arch. Gen. Psychiatry,1976
3. Affective illness in veteran twins: A diagnostic review;Allen;Am. J. Psychiatry,1974
4. The Broken Brain;Andreasen,1984
5. A Danish twin study of manic-depressive disorders;Bertelsen;Br. J. Psychiatry,1977