Forgotten twins.
Segal
N L
NL
D004200:Diseases in Twins / Q000235:genetics*; D005260:Female; D006801:Humans; D008297:Male; D011247:Pregnancy; D011256:Pregnancy Outcome; D011272:Pregnancy, Multiple; D018433:Twin Studies as Topic; D014429:Twins, Dizygotic / Q000235:genetics / Q000523:psychology