00338nam a2200109Ia 4500008004100000040001100041100002100052245008300073260004700156300001600203300000900219251112s9999||||xx |||||||||||||| ||und||  aCNCLSA  aLawrence Bogorad 0aProceedings Of The National Academy Of Science Of The United States Of America  c1990bNational Academy Of ScienceaU. S. A  aP.3088-4050  bV.99