War Journal of Franz Halder

Generaloberst Franz Halder was Chief of the General Staff of the Supreme Command of the German Army (OKH), 14 August 1939 to 24 September 1942. His private war journal is available online:

World War II Operational Documents

Abstract: This private war journal comprises seven volumes covering the dates 14 August 1939 to 24 September 1942, the date of Halder's dismissal by Hitler. The journal was kept by Halder personally in his own shorthand and contains notes on conferences, memoranda, staff talks, lectures, reports, etc., as they occurred during the discharge of his function as Chief of Staff.

Volume IV includes the invasion of France in 1940. Here's a little screenshot:

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