00307nam a2200121Ia 450000500170000000800410001704100080005808200150006610000180008124500390009926000380013830000090017620260720174550.0260720s2004    xx            000 0 und d  aeng  a372.8 KUMT  aKumar, Arvind  aTextbook of enviournmental science  aNew DelhibA P H Publishingc2004  a376p