00293nam a2200097Ia 4500008004100000082001900041100002200060245007600082260003000158300000700188140113s9999    xx            000 0 und d  a631(082.1)   L  a"Herderson, A.J."  a"Better Farming series - 10  conserving the soil,  improving the soil "  a1970bFAOcUnited Nations  a30