1. National Bureau of Standards , “Data Encryption Standard,” Federal Information Processing Standards Publication 46, US Government Printing Office, Washington, DC (1977).
2. National Bureau of Standards , “Data Encryption Standard Modes of Operation,” Federal Information Processing Standards Publication 81, US Government Printing Office, Washington, DC, (1980).
3. Optical image encryption based on input plane and Fourier plane random encoding
4. Optical encryption system that uses phase conjugation in a photorefractive crystal
5. Optical implementation of image encryption using random phase encoding