National Fire Protection Association (Estados Unidos), American Gas Association, Ing, A., & Marando, M. (2020). National fuel gas code handbook (Eleventh edition.). Quincy, Massachusetts: National Fire Protection Association.
Citación estilo ChicagoNational Fire Protection Association (Estados Unidos), American Gas Association, Alex Ing, y Mike Marando. National Fuel Gas Code Handbook. Eleventh edition. Quincy, Massachusetts: National Fire Protection Association, 2020.
Cita MLANational Fire Protection Association (Estados Unidos), American Gas Association, Alex Ing, y Mike Marando. National Fuel Gas Code Handbook. Eleventh edition. Quincy, Massachusetts: National Fire Protection Association, 2020.
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