Tom Head. The Set of Strings Mapped Into a Submonoid by Iterates of a Morphism. Theoretical Computer Science, 73(3):329-333, 1990.
@article{Head90, title = {The Set of Strings Mapped Into a Submonoid by Iterates of a Morphism}, author = {Tom Head}, year = {1990}, researchr = {https://researchr.org/publication/Head90}, cites = {0}, citedby = {0}, journal = {Theoretical Computer Science}, volume = {73}, number = {3}, pages = {329-333}, }