Design of Sequential Machines from Their Regular Expressions. - Gene Ott; Neil H. Feinstein (J. ACM, 1961)

Compact encoding of stationary Markov sources. - Gene Ott (IEEE Trans. Inf. Theory, 1967)

Ambiguity in Graphs and Expressions. - Ronald Vernon Book; Shimon Even; Sheila A. Greibach; Gene Ott (IEEE Trans. Computers, 1971)