, амер. работники добывающей отрасли*
See:
Standard Occupational Classification System, Derrick, Rotary Drill, and Service Unit Operators, Oil, Gas, and Mining, Derrick, Rotary Drill, and Service Unit Operators, Oil, Gas, and Mining, Derrick, Rotary Drill, and Service Unit Operators, Oil, Gas, and Mining, Derrick, Rotary Drill, and Service Unit Operators, Oil, Gas, and Mining, Derrick, Rotary Drill, and Service Unit Operators, Oil, Gas, and Mining, Derrick, Rotary Drill, and Service Unit Operators, Oil, Gas, and Mining, Derrick, Rotary Drill, and Service Unit Operators, Oil, Gas, and Mining, Derrick, Rotary Drill, and Service Unit Operators, Oil, Gas, and Mining, Derrick, Rotary Drill, and Service Unit Operators, Oil, Gas, and Mining