000 00311pam a2200133a 44500
082 _aBTS
_bMONO 1920
100 _aRiordan,John
245 1 _aTELEPHONE TRAFFIC TIME AVERAGES
260 _a
_b
_c1951
300 _a16
500 _aBound With Bts Mono 1900-19,1921-29
964 _gCIRC
997 _aTR19694 C
999 _c403414
_d403414