[On the twin method of studying oligophrenia].
D000293:Adolescent; D004200:Diseases in Twins; D004777:Environment; D005260:Female; D006801:Humans; D008607:Intellectual Disability / Q000209:etiology / Q000235:genetics*; D008297:Male; D012959:Socioeconomic Factors
O bliznetsovom metode izucheniia obligofreniĭ.