000 00302nam a2200121 4500
008 160616s 000 0
245 _aSystems of requency curves
100 _aElderton, William Palin
100 _aJohnson, Norman Lloyd
500 _aB627 K9
942 _cBK
_2BK3361
080 _a514.144 ELD
999 _c3361
_d3361