U.S. Customs and Border Protection
Official Site
U.S. Customs Air and Marine Operations
Immigration Act of 1924 Summary
Immigration Act of 1924 Full Text
Operation "Hold the Line" 1993
Produced by the El Paso Museum of History
New York Times article on Operation "Hold the Line"
Los Angeles Times article on Operation "Gatekeeper"
Operation Gatekeeper: An Investigation into Allegations of Fraud and Misconduct
Inspector General report from the Department of Justice