000 00252pam a2200109a 44500
082 _aTR
_bRI-9220
100 _aThomas M. Barczak
245 1 _aTwo-leg longwall shield mechanics
260 _a
_b
_c
700 _aDavid E. Schwemmer
997 _aTR6595 C
999 _c405761
_d405761