00304nam a2200121Ia 450000500170000000800410001704100080005808200150006610000150008124500390009626000380013530000090017320260720174537.0260720s2005    xx            000 0 und d  aeng  a372.8 SINT  aSingh, U K  aTeaching of enviournmental science  aNew DelhibA P H Publishingc2005  a383p