000 00311nam a2200121Ia 4500
008 191031s9999 xx 000 0 und d
100 _aRobertson
245 0 _aIntroduction to agricultural production economics and farm management
260 _bMcGraw Hill
260 _c1977
365 _b6.50
942 _cBK
999 _c206385
_d206385