APA

Gas Processors Association G., . (1981). Tentative reference bulletin heating value as a basis for custody transfer of natural gas. Tulsa, Oklahoma: Gas Processors Association, GPA.

Chicago

Gas Processors Association GPA, . 1981. Tentative reference bulletin heating value as a basis for custody transfer of natural gas. Tulsa, Oklahoma: Gas Processors Association, GPA.

Harvard

Gas Processors Association G., . (1981). Tentative reference bulletin heating value as a basis for custody transfer of natural gas. Tulsa, Oklahoma: Gas Processors Association, GPA.

MLA

Gas Processors Association GPA, . Tentative reference bulletin heating value as a basis for custody transfer of natural gas. Tulsa, Oklahoma: Gas Processors Association, GPA. 1981.