Front Cover Oliver G. Wood, Robert J. Porter. "National Bank Surveillance System". Google Books. Van Nostrand Reinhold Co. p. 9. Retrieved 23 May 2012.
fdic.gov
"Off Site Survillance Systems"(PDF). An examination of the banking crises of the 1980s and early 1990s. History of the Eighties:Lessons for the future. Retrieved 23 May 2012.