000 00311nam a2200133Ia 4500
008 220421s9999||||xx |||||||||||||| ||und||
040 _aET
100 _ashukal acharya ramchandra
245 0 _awaves & OSCI Lation(optics)
260 _bkhosla pub.h.
_aDelhi
300 _a208
500 _a60633
942 _cBK
999 _c66596
_d66596