1. Ferrier, S.: Enfant mongolien-parent mosaique. Étude de deux familles. J. Genet. Hum. 13, 315?336 (1964)
2. CIBA Foundation Study Group;H. Forssman,1967
3. Greenberg, R. C.: Two factors influencing the births of mongols to younger mothers. Med. Offr. 109, 62?64 (1963)
4. Hara, Y., Sasaki, M.: A note on the origin of the extra chromosomes in trisomies 13 and 21. Proc. Japan Acad. 51, 295?299 (1975)
5. Hsu, L. Y. F., Gertner, M., Leitner, E., Hirschhorn, K.: Paternal trisomy 21 mosaicism and Down's syndrome. Am. J. Hum. Genet. 23, 592?601 (1971)