: An expanded second edition by Seweryn Fleischer and Marek Ryś, published by AJ-Press in 2004. This is a comprehensive technical and historical reference.
: You can find free downloads of historical photographs, such as a 1945 photo of the Ar 234 on display, via the Internet Archive . Download Gorman Arado 234 Blitz rar
: Various sites like epdf.pub host PDF versions of aircraft handbooks and variants, which might be the "download" you are looking for. Modeling and Spec Sheets : An expanded second edition by Seweryn Fleischer