00342nam a2200109Ia 4500008004100000040001100041100002700052245008400079260004200163300001600205300001100221251112s9999||||xx |||||||||||||| ||und||  aCNCLSA  aNicholas R. Cozzarelli 0aProceedings of the National Academy Of Sciences of the United States of America  cMay 5, 1990bpergamon pressaNew York  aP. 607-1138  bV. 213