I think it is in one of the books written by former Lt. Gen Ion Pacepa. Here is a link to an interview in which he talks about the Soviet disinformation campaign against Pope Pius XII
http://www.theblaze.com/blog/2014/02/10/an-interview-with-lt-gen-ion-pacepa-the-highest-ranking-soviet-bloc-intel-officer-to-ever-defect/
Thanks so much! <3