Não informado. (2018). Petroleum Equipment and Services. Associated Publishers.
Παραπομπή σε μορφή Chicago (17η εκδ.)Não informado. Petroleum Equipment and Services. Dallas, Tex: Associated Publishers, 2018.
Παραπομπή σε μορφή MLA (8th εκδ.)Não informado. Petroleum Equipment and Services. Associated Publishers, 2018.
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