000 00402nam a2200121Ia 4500
001 MPKV059091
008 120911s9999 xx 000 0 und d
082 _a630
245 _aProceedings of the National Academy of Sciences Vol.52-1
_c;
246 _aProceedings of the National Academy of Sciences Vol.52-1
260 _aUSA
_bNational Academy of Science
_c1964
650 _aAgronomy/General Agricultural
999 _c57079
_d57079