Mark Daley, Michael Domaratzki, Kai Salomaa. Orthogonal Concatenation: Language Equations and State Complexity. J. UCS, 16(5):653-675, 2010. [doi]
@article{DaleyDS10,
title = {Orthogonal Concatenation: Language Equations and State Complexity},
author = {Mark Daley and Michael Domaratzki and Kai Salomaa},
year = {2010},
doi = {10.3217/jucs-016-05-0653},
url = {http://dx.doi.org/10.3217/jucs-016-05-0653},
researchr = {https://researchr.org/publication/DaleyDS10},
cites = {0},
citedby = {0},
journal = {J. UCS},
volume = {16},
number = {5},
pages = {653-675},
}