000 00315nam a22001097a 4500
082 _a507
_bP17
084 _2Colon Classification
100 _aChopra, J K
245 _aGeneral Science and technology: For UPSC civil services preliminary examinations
260 _aNew Delhi
_bUnique Publication
_c2017
942 _cBK
999 _c220338
_d220338