title: [INVESTIGATIONS ON "DIFFICULT SUBJECTS"].
mesh_terms: D004467:Economics; D006801:Humans; D008393:Marriage; D011584:Psychology; D012725:Sexual Behavior; D012961:Sociology
keywords: ECONOMICS; MARRIAGE; PSYCHOLOGY; SEX BEHAVIOR; SOCIOLOGY
vernacular_title: ENQU ETEREN OVER "MOEILIJKE ONDERWERPEN".