000 00287pam a2200109a 44500
082 _aTR
_bRI-9377
100 _aE. K. Hjelmstad
245 1 _aUltra loue frequency electromagnetic fire alarm system for underground mines
260 _a
_b
_c
700 _aH. W. Pomroy
997 _aTR6759 C
999 _c405916
_d405916