000 00288pam a2200109a 44500
082 _aTR
_bRI-8142
100 _aRobert P. Vinson
245 1 _aThree coal mine ventilation studies using sulfur hexaflusoride tracer gas
260 _a
_b
_c
700 _aFred N. Kissell
997 _aTR2051 C
999 _c404765
_d404765