000 00286nam a2200121 4500
020 _a978-8171415687
022 _a8171415687
100 _a D.B. Rao
245 _aScience and Technology Education
260 _aNew Delhi
_bDiscovery Publishing House
_c2020
300 _a557
942 _cBK
999 _c4358
_d4358