00335nam a2200121Ia 4500008004100000082002200041100001800063245005300081260002500134300000900159600001600168650002900184140224s9999    xx            000 0 und d  aPH 621.223(02) K7  aHamm, Hans W.  aLow cost development of small water power sites.  aMarylandbVITAc1967  a43p.  aHans W.Hamm  aWater power,Water wheels