Columbia subject headings:
Harvard subject headings:
Energy industries--Statistics--Periodicals.
Energy industries--United States--Statistics--Periodicals.
Gas industry--Statistics--Periodicals.
Gas industry--United States--Statistics--Periodicals.
Petroleum industry and trade--Statistics--Periodicals.
Petroleum industry and trade--United States--Statistics--Periodicals.
Princeton subject headings:
Energy industries--Statistics--Periodicals.
Energy industries--United States--Statistics--Periodicals.
Gas industry--Statistics--Periodicals.
Gas industry--United States--Statistics--Periodicals.
Periodicals.
Petroleum industry and trade--Statistics--Periodicals.
Petroleum industry and trade--United States--Statistics--Periodicals.
Statistics.