Vesa Halava, Jarkko Kari, Yuri Matiyasevich. On post correspondence problem for letter monotonic languages. Theoretical Computer Science, 410(30-32):2957-2960, 2009. [doi]
@article{HalavaKM09,
title = {On post correspondence problem for letter monotonic languages},
author = {Vesa Halava and Jarkko Kari and Yuri Matiyasevich},
year = {2009},
doi = {10.1016/j.tcs.2009.01.040},
url = {http://dx.doi.org/10.1016/j.tcs.2009.01.040},
researchr = {https://researchr.org/publication/HalavaKM09},
cites = {0},
citedby = {0},
journal = {Theoretical Computer Science},
volume = {410},
number = {30-32},
pages = {2957-2960},
}