60s WWII German secret weapons, airplanes/rockets illustrations/photos

1969 edition of German Secret Weapons Blueprint for Mars - book No 5 of Ballantine's Illustrated History of World War Two. This has about 160 pages with tons of photos and illustrations of of German secret weapon development plans and projects during the second World War.

This covers the famous V2 rocket, the first ground to air guided missile, early jet engine fighter aircraft, vertical takeoff aircraft, predecessors of the American stealth airplanes and much more!

We're not sure what the story is on Mars in the title? While flipping through the book, we didn't see any reference to Mars.

This has wear and the front hinge is cracked.