1. Berstel, J., Reutenauer, C.: Noncommutative Rational Series With Applications. In: Encyclopedia of Mathematics and its Applications, vol. 137. Cambridge University Press, Cambridge (2010)
2. Bloom, S.L., Ésik, Z.: Matrix and matricial iteration theories, Parts I and II. J. Comput. Sys. Sci. 46, 381–408, 409–439 (1993)
3. EATCS Monographs on Theoretical Computer Science;S.L. Bloom,1993
4. Bloom, S.L., Ésik, Z.: Axiomatizing rational power series over natural numbers. Information and Computation 207, 793–811 (2009)
5. Bloom, S.L., Ésik, Z., Kuich, W.: Partial Conway and iteration semirings. Fundamenta Informaticae 86, 19–40 (2008)