Não informado. (1903). Circular of the Bureau of Standards. U.S. Department of Commerce, National Bureau of Standards.
Citação do estilo Chicago (17ª ed.)Não informado. Circular of the Bureau of Standards. Washington: U.S. Department of Commerce, National Bureau of Standards, 1903.
Citação MLA (8ª ed.)Não informado. Circular of the Bureau of Standards. U.S. Department of Commerce, National Bureau of Standards, 1903.
Atenció: Aquestes cites poden no estar 100% correctes.