Looking for Adolf, Volume 1

[ben]

[Jeffbert]

[Jeffbert]

I receive ABOUT.COM'S 20th Century History email updates, & just today, the above headline was sent.



However, the page sites no sources. The following page does cite a source:



Which is this UK newspaper:



So, the question is, what basis did Tezuka have for this plot element in ADOLF? If there was no obvious element in the known family tree (see link in first page cited), why would Tezuka even suspect such a thing? Was it merely Tezuka's imagination that produced this plot element?