An Empirical Method for Finding the Keylength of periodic Ciphers. - Robert A. J. Matthews (Cryptologia, 1988)

On the Derivation of a "Chaotic" Encryption Algorithm. - Robert A. J. Matthews (Cryptologia, 1989)

A Rotor Device for Periodic and Random-Key Encryption. - Robert A. J. Matthews (Cryptologia, 1989)

Supercomputer Investigations of a Chaotic Encryption Algorithm. - Daniel D. Wheeler; Robert A. J. Matthews (Cryptologia, 1991)

The Use of Genetic Algorithms in Cryptanalysis. - Robert A. J. Matthews (Cryptologia, 1993)