00325nam a22001217a 4500082000900000100001600009245008800025260002900113300001800142526001800160650001100178700001400189  aT-36  aAhsan Bilal  aPerformance study of vertical upward flow coarse media roughing filtercAhsan Bilal  aRisalpurbMCEc25-5-1996  a109p.:c40cm.  a0b0c0dT_36  aThesis  awaris ali