Gaya APA

Service., P, E. (1971). Lessons in well servicing and workover. lesson 6. production rig equipment. (1971). : Texas : Petroleum Extension Service,.

Gaya MLA

Service., Petroleum, Extension. "Lessons in well servicing and workover. lesson 6. production rig equipment.". 1971 : Texas : Petroleum Extension Service,, 1971. Text.