Meera Blattner, Tom Head. Automata That Recognize Intersections of Free Submonoids. Inf. Comput., 35(3):173-176, November 1977.
@article{BlattnerH77, title = {Automata That Recognize Intersections of Free Submonoids}, author = {Meera Blattner and Tom Head}, year = {1977}, month = {November}, researchr = {https://researchr.org/publication/BlattnerH77}, cites = {0}, citedby = {0}, journal = {Inf. Comput.}, volume = {35}, number = {3}, pages = {173-176}, }