000 00335nam a2200121Ia 4500
008 191031s9999 xx 000 0 und d
100 _aRyn (James Garrett)
245 0 _aGeneralized crop fertilizer production functions
260 _b"Natioal Technicla Information Service, USA"
260 _c1972
365 _b102.00
942 _cBK
999 _c204504
_d204504