The content of this website has been compiled from a wide range of primary and secondary sources. These include official battle reports, operational records, contemporary documents, personal accounts and memoirs, published studies, and historical monographs.
The number of official battle reports consulted alone runs into the thousands, making it impractical to list each individual document. Dutch battle reports constitute the largest body of material, but all available German operational records - particularly the Kriegstagebücher (KTBs, War Diaries) - have also been consulted, together with a substantial collection of French military reports.
A large number of historical studies have been used, ranging from analyses published shortly after the war to more recent academic research. Less well-known works by Jacobsen, Dr. Weiss, General Hans von Speidel, and Oberst Langmann have all been consulted. Although some of these studies inevitably reflect the perspectives or limitations of their time, they remain valuable sources. Dutch military studies by Generals Van Hilten and Nierstrasz have likewise been used where appropriate, alongside lesser-known publications produced by military research institutes.
Memoirs by leading German participants - including Kurt Student, Albert Kesselring, Franz Halder, and Hasso von Manteuffel - have provided valuable insights into German operational planning and decision-making. Students memoirs obviously added to the German side of the airborne operation in the Netherlands.
More recent publications have also proved indispensable, particularly Karl-Heinz Golla's work on the Fallschirmjäger operations of 1939–1941 and Karl-Heinz Frieser's seminal study of the origins and execution of Blitzkrieg. The author has maintained a long-standing exchange of research findings with Karl-Heinz Golla, resulting in the mutual sharing of new information, sources, and interpretations and a large contribution to the English-version of his work about the German airbornes in the 1936-1941 episode ("The German Fallschirmtruppe 1936-1941").
In total, more than 200 books dealing wholly or partly with the May 1940 campaign have been consulted. Some have served primarily as guides to additional archival material, while others have contributed unique facts, analyses, or statistical data. Secondary sources are indispensable in directing the researcher towards relevant primary material and in helping to assess the reliability of conflicting accounts.
The work of the late Lieutenant-Colonel (Ret.) E.H. Brongers has been particularly valuable in providing direction for further research. Equally important is the official Dutch military history of the May 1940 campaign, published between 1950 and 1970 under the editorship of the late Major-General (Ret.) V.E. Nierstrasz. Although both works have their limitations and occasionally reflect the historiographical context in which they were written, together they present a broadly comprehensive account of the campaign.
Finally, the author has drawn extensively upon his own research library, previous publications, and decades of archival study. His work has focused primarily on the Dutch defence of the Maas front, the German campaign against the Netherlands and Belgium, and the operations of the French Army on Dutch soil during the May 1940 campaign.