Não informado. Environmental Pollution and Control. U.S. Department of Commerce, National Technical Information Service.
Citação do estilo Chicago (17ª ed.)Não informado. Environmental Pollution and Control. Springfield, Va: U.S. Department of Commerce, National Technical Information Service.
Citação MLA (8ª ed.)Não informado. Environmental Pollution and Control. U.S. Department of Commerce, National Technical Information Service.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.