PETEX. (1982). Basic tools land equipment for the oil field - Petex. The universary of texas.
Chicago-viite (17. p.)PETEX. Basic Tools Land Equipment for the Oil Field - Petex. The universary of texas, 1982.
MLA-viite (8. p.)PETEX. Basic Tools Land Equipment for the Oil Field - Petex. The universary of texas, 1982.
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