00273nam a2200097Ia 4500008004100000040001100041245005100052260004700103300001600150300000900166251112s9999||||xx |||||||||||||| ||und||  aCNCLSA 0aProceedings Of The National Academy Of Science  c1982bNational Academy Of ScienceaU. S. A  aP.6745-7828  bV.79