73526544
Mar 12, 1985
Jul 15, 1986
COMPUTER PROGRAMS RECORDED ON TAPES, CARDS, OR DISCS; COMPUTER PROGRAMS PERMITTING ONE TO EFFECT VENTILATING CALCULATIONS IN UNDERGROUND MINE OR QUARRY EXPLOITATIONS
Electrical and Scientific ApparatusCOMPUTER PROGRAMMING; SOFTWARE DEVELOPMENT; ENGINEERING, RESEARCH, SURVEILLANCE, AND INSPECTION SERVICES IN THE UNDERGROUND MINE AND QUARRY EXPLORATION FIELD
Computer and Scientific