Reference:

Nikola Benes, Jan Kretinsky, Kim Guldstrand Larsen, and Jiri Srba. Checking thorough refinement on modal transition systems is exptime-complete. In ICTAC, pages 112–126, 2009.

Suggested BibTeX entry:

@inproceedings{DBLP:confictacBenesKLS09,
    author = {Nikola Benes and Jan Kretinsky and Kim Guldstrand Larsen and Jiri Srba},
    booktitle = {ICTAC},
    pages = {112-126},
    title = {Checking Thorough Refinement on Modal Transition Systems Is EXPTIME-Complete},
    year = {2009}
}