As with the previous titles, Jentz and Doyle have eschewed all secondary sources and have researched their book strictly in the archival documents of the design, manufacturing, and assembly firms such as Krupp, Henschel, Porsche, and Wegmann. If it couldn't be found in an original document, photograph, or surviving Tiger, it isn't in this book. The sources of information are stated in the text. Those desiring footnotes and an extensive bibliography are advised to look elsewhere. The goal is to create an accurate record of events, not prove that a list of over 200 publications can be accumulated.
Events occur in only one way.
A clear picture of these events cannot be obtained from stories, military intelligence reports, expert opinion, analyses of raw data, or secondary sources. Either the events were recorded by a participant or they weren't. Unfortunately some key records, such as Krupp's correspondence on the design of their turret for the period from June to December 1941, didn't survive the war. Thus the story of the evolution of the turret designed by Krupp for the Porsche Tiger will never be known. No amount of conjecture, supposition, reasoning, or opinion can fill gaps like this in the original records.