APA
American Petroleum Institute A., . (2021). Steel gate valves -Flanged and but-welding ends, bolted bonnets. Washington: American Petroleum Institute, API.
Chicago
American Petroleum Institute API, . 2021. Steel gate valves -Flanged and but-welding ends, bolted bonnets. Washington: American Petroleum Institute, API.
Harvard
American Petroleum Institute A., . (2021). Steel gate valves -Flanged and but-welding ends, bolted bonnets. Washington: American Petroleum Institute, API.
MLA
American Petroleum Institute API, . Steel gate valves -Flanged and but-welding ends, bolted bonnets. Washington: American Petroleum Institute, API. 2021.