Google Books, Ingelbart, Louis Edward, Press Freedoms. A Descriptive Calendar of Concepts, Interpretations, Events, and Courts Actions, from 4000 B.C. to the Present, Greenwood Publishing 1987, ISBN 0-313-25636-5]
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Ingelbart, Louis Edward, Press Freedoms. A Descriptive Calendar of Concepts, Interpretations, Events, and Courts Actions, from 4000 B.C. to the Present, p40, Greenwood Publishing 1987, ISBN 0-313-25636-5, [1]
