Axiomatizing rational power series over natural numbers

@article{Bloom2009AxiomatizingRP,
  title={Axiomatizing rational power series over natural numbers},
  author={Stephen L. Bloom and Zolt{\'a}n {\'E}sik},
  journal={Inf. Comput.},
  year={2009},
  volume={207},
  pages={793-811}
}