ARPANET and related projects - from DARPA Technical Accomplishments An Historical Review of DARPA Projects, IDA Paper P-2192, 1990.
Sidney G. Reed, Richard H. Van Atta, and Seymore J. Deitchman
1989
<p>"ARPANET", in <i><a rel="nofollow" class="external text" href="https://apps.dtic.mil/dtic/tr/fulltext/u2/a239925.pdf">DARPA Technical Accomplishments: An Historical Review of DARPA Projects</a></i>, vol. 1, Chapter 20, by Sidney G. Reed, Richard H. Van Atta, and Seymore J. Deitchman, IDA Paper P-2192, 1990. This particular figure was published in 1989 or earlier. Available online:
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