00348nam a22001217a 4500082001300000100001300013245004800026260001800074300000800092942000700100999001700107952010200124  a631.6ROB  aRobert B  aPerformance of subsurface drainage systems   aCanada c1972  a215  cBK  c13045d13045  001040708REFaREFbREFd2015-04-14l0o631.6ROB   (Shelf - 75C)p9093r2015-04-14 00:00:00yBK