00292nam a2200097Ia 4500008004100000082002000041100004100061245004000102260004400142300000800186140113s9999    xx            000 0 und d  a577.14:312   L2  a"Enrich, Paul. R. & Enrich, Anne H."  a"Population, Rsources, Environment"  a1972bW.H.Freeman & Co.cSan Franscisco  a509