00283nam a2200097Ia 4500008004100000040001100041245005100052260005700103300001600160300000900176251112s9999||||xx |||||||||||||| ||und||  aCNCLSA 0aProceeding of the national academy of sciences  cDecember, 1986bNational Academy Of ScienceaU. S. A  aP.8819-9975  bV.83