Originally published as: Hitler's espionage machine : the true story behind one of the world's most ruthless spy networks. Guiford, CT : Lyons Press, 2004.
Spying for the Führer : Hitler's espionage machine by Christer Jörgensen. ISBN 9781473823068. Published by Pen & Sword Military in 2014. Publication and catalogue information, links to buy online and reader comments.