Maurice Nivat, Andreas Podelski. Minimal Ascending and Descending Tree Automata. SIAM Journal on Computing, 26(1):39-58, 1997.
@article{NivatP97, title = {Minimal Ascending and Descending Tree Automata}, author = {Maurice Nivat and Andreas Podelski}, year = {1997}, researchr = {https://researchr.org/publication/NivatP97}, cites = {0}, citedby = {0}, journal = {SIAM Journal on Computing}, volume = {26}, number = {1}, pages = {39-58}, }