金工作
Stafford, David. Spies Beneath Berlin - the Extraordinary Story of Operation Stopwatch/Gold, the CIA's Spy Tunnel Under the Russian Sector of Cold War Berlin Overlook Press, 2002. ISBN 1-58567-361-7
David E. Murphy, Sergei A. Kondrashev, George Bailey. Battleground Berlin: CIA vs. KGB in the Cold War Yale University Press, 1999. ISBN 0-300-07233-3