1. Makino and Takagi, 1965
2. Chapelle et;la, De,1963
3. Gripenberg, 1964
4. Aggressive behaviour, mental subnormality and the XYY male;McClemont, W.F.;Nature (London),1965
5. personal communication, cited in Penrose, L. S;McClemont, W.F.; Hamden, D.G.;Mongolism. British Medical Bulletin,1961