00306nam a2200097Ia 4500008004100000040001100041245008400052260004700136300001600183300000900199251112s9999||||xx |||||||||||||| ||und||  aCNCLSA 0aProceedings Of The National Academy Of Sciences Of The United States Of America  c1993bNational Academy Of ScienceaU. S. A  aP.7909-8758  bV.90