Gaya APA

Service, P, E. (1971). Lessons in well servicing and workover lesson 12. well service and workover profitability. (1971). : Texas: Petroleum Extension Service,.

Gaya MLA

Service, Petroleum, Extension. "Lessons in well servicing and workover lesson 12. well service and workover profitability.". 1971 : Texas: Petroleum Extension Service,, 1971. Text.