Apollo Movie Guide - The Ipcress File: Review, links, and cast information.
Britmovie: The Ipcress File: Cast, images and synopsis.
IMDb - The Ipcress File (1965): Plot synopsis, list of cast and crew, and user ratings.
The New York Times: The Ipcress File: Review by Bosley Crowther.
TV Guide Online: The Ipcress File: Brief review and credits.