1. K.B. Arkhangelskii and P.V. Gorshkov. Implicational axioms for the algebra of regular languages (in Russian). Doklady Akad. Nauk, USSR, ser A., 10:67–69, 1987.
2. S. L. Bloom and R. Tindell. A note on zero congruences. Acta. Cybernetica, 8:1–4, 1987.
3. S.L. Bloom, C.C. Elgot, and J.B. Wright. Solutions of the iteration equation and extensions of the scalar iteration operation. SIAM Journal of Computing, 9:26–45, 1980.
4. S.L. Bloom, C.C. Elgot, and J.B. Wright. Vector iteration in pointed iterative theories. SIAM Journal of Computing, 9:525–540, 1980.
5. S.L. Bloom and Z. Ésik. Matrix and matricial iteration theories, Part I. Journal of Computer and System. Sciences. 46:381–408, 1993.