Gaya APA

Bungert, H, %, J, G, %. (). Secret Intelligence in the Twentieth Century . [Washington DC]: [Centre for Counterintelligence and Security Studies].

Gaya MLA

Bungert, Heike, %6aHeitmann,, Jan, G., %. "Secret Intelligence in the Twentieth Century". [Washington DC]: [Centre for Counterintelligence and Security Studies], . Buku.