00294nam a2200097Ia 4500008004100000082001900041100004200060245004800102260003800150300000800188140113s9999    xx            000 0 und d  a631.461.5   L1  a"Mishustin, E.N. & Shil-Nikova, U.K."  aBiological Fixation of Atmospheric Nitrogen  a1971bMacmillan & Co.Ltd.cLondon  a420