1. An analysis of family data on 1,000 patients admitted to a Canadian mental hospital;Gregory;Acta Genetica et Statistica Medica,1959
2. Die Beziehung der Schizophrenic zum Alter der Eltern der Patienten;Bojanovsky;Der Nervenarzt,1967
3. Relation between maternal age at parturition and incidence of mental disorder in the offspring;Goodman;British Journal of Preventive and Social Medicine,1957
4. Raised Parental Age in Psychiatric Patients: Evidence for the Constitutional Hypothesis