title: Twin research. Proceedings of the Second International Congress on Twin Studies August 29--September 1, 1977, Washington, DC. Part B. Biology and epidemiology.
mesh_terms: D003226:Congresses as Topic; D004200:Diseases in Twins; D005060:Europe; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D011247:Pregnancy; D011272:Pregnancy, Multiple; D012106:Research; D014427:Twins; D014481:United States