APA

United States, . (1973). Factors affecting use of coal in present and future energy markets: background paper by Congressional Research Service pursuant to S. Res. 45, national fuels and energy policy study. [Washington, D.C.]: .

Chicago

United States, . 1973. Factors affecting use of coal in present and future energy markets: background paper by Congressional Research Service pursuant to S. Res. 45, national fuels and energy policy study. [Washington, D.C.]: .

Harvard

United States, . (1973). Factors affecting use of coal in present and future energy markets: background paper by Congressional Research Service pursuant to S. Res. 45, national fuels and energy policy study. [Washington, D.C.]: .

MLA

United States, . Factors affecting use of coal in present and future energy markets: background paper by Congressional Research Service pursuant to S. Res. 45, national fuels and energy policy study. [Washington, D.C.]: . 1973.