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Ida Tarbell was an American professor, writer and journalist, considered one of the main "muckrakers" of the Progressive Era of the late nineteenth and early twentieth century and a pioneer of investigative journalism.
She is known for her research on John D. Rockefeller and the Standard Oil Company, published in series by McClure's Magazine from 1902 to 1904; her investigations exposed the unfair monopolistic practices practiced by the company until the Supreme Court of the United States decided to dissolve the monopoly.