@article(Alberucci_Facchini2009:transitive_reflexive,
 author       = "Luca Alberucci and Alessandro Facchini",
 year         = "2009",
 title        = "The modal $\mu $-calculus over restricted classes of transition systems",
 journal      = "J.\spacefactor \@m Symb.\spacefactor \@m Log.\spacefactor \@m ",
 volume       = "74",
 number       = "4",
 pages        = "1367--1400",
 doi          = "10.2178/jsl/1254748696",
)
@article(Alur2009,
 author       = "Rajeev Alur and P. Madhusudan",
 year         = "2009",
 title        = "Adding Nesting Structure to Words",
 journal      = "J.\tmspace +\thinmuskip {.1667em}ACM",
 volume       = "56",
 number       = "3",
 pages        = "1--43",
 doi          = "10.1145/1516512.1516518",
)
@article(Arenas_Barcelo_Libkin2011:nestedwords,
 author       = "Marcelo Arenas and Pablo Barcel{\'o} and Leonid Libkin",
 year         = "2011",
 title        = "Regular Languages of Nested Words: Fixed Points, Automata, and Synchronization",
 journal      = "Theor.\spacefactor \@m Comput.\spacefactor \@m Syst.\spacefactor \@m ",
 volume       = "49",
 number       = "3",
 pages        = "639--670",
 doi          = "10.1007/s00224-010-9292-5",
)
@article(RAIRO:arnold99,
 author       = "Andr{\'e} Arnold",
 year         = "1999",
 title        = "The modal $\mu $-calculus alternation-depth is strict on binary trees",
 journal      = "Theor. Inform. Appl.",
 volume       = "33",
 number       = "4--5",
 pages        = "329--339",
 doi          = "10.1051/ita:1999121",
)
@book(an01,
 author       = "Andr{\'e} Arnold and Damian Niwi{\'n}ski",
 year         = "2001",
 title        = "Rudiments of $\mu $-calculus",
 series       = "Studies in Logic and the Foundations of Mathematics",
 volume       = "146",
 publisher    = "North-Holland",
)
@inproceedings(Bozzelli2007:nestedwords,
 author       = "Laura Bozzelli",
 year         = "2007",
 title        = "Alternating Automata and a Temporal Fixpoint Calculus for Visibly Pushdown Languages",
 booktitle    = "CONCUR'07",
 series       = "Lect.\spacefactor \@m Notes Comput.\spacefactor \@m Sci.\spacefactor \@m ",
 volume       = "4703",
 pages        = "476--491",
 doi          = "10.1007/978-3-540-74407-8\_32",
)
@article(Bradfield1998:mucalculus_strict,
 author       = "Julian C. Bradfield",
 year         = "1998",
 title        = "The modal mu-calculus alternation hierarchy is strict",
 journal      = "Theoret.\spacefactor \@m Comput.\spacefactor \@m Sci.\spacefactor \@m ",
 volume       = "195",
 number       = "2",
 pages        = "133--153",
 doi          = "10.1016/S0304-3975(97)00217-X",
)
@article(Bradfield99-binarytree,
 author       = "Julian C. Bradfield",
 year         = "1999",
 title        = "Fixpoint alternation: arithmetic, transition systems, and the binary tree",
 journal      = "Theor. Inform. Appl.",
 volume       = "33",
 number       = "4--5",
 pages        = "341--356",
 doi          = "10.1051/ita:1999122",
)
@article(DAgostino_Lenzi2010:transitive,
 author       = "Giovanna D'Agostino and Giacomo Lenzi",
 year         = "2010",
 title        = "On the $\mu $-calculus over transitive and finite transitive frames",
 journal      = "Theoret.\spacefactor \@m Comput.\spacefactor \@m Sci.\spacefactor \@m ",
 volume       = "411",
 number       = "50",
 pages        = "4273--4290",
 doi          = "10.1016/j.tcs.2010.09.002",
)
@article(Dawar_Otto2009:modal_characterizations,
 author       = "Anuj Dawar and Martin Otto",
 year         = "2009",
 title        = "Modal characterisation theorems over special classes of frames",
 journal      = "Ann. Pure Appl. Logic",
 volume       = "161",
 number       = "1",
 pages        = "1--42",
 doi          = "10.1016/j.apal.2009.04.002",
)
@inproceedings(Emerson_Jutla:focs1991,
 author       = "E. Allen Emerson and Charanjit S. Jutla",
 year         = "1991",
 title        = "Tree Automata, Mu-Calculus and Determinacy",
 booktitle    = "FOCS'91",
 pages        = "368--377",
 doi          = "10.1109/SFCS.1991.185392",
)
@inproceedings(Emerson_Lei:lics1986,
 author       = "E. Allen Emerson and Chin-Laung Lei",
 year         = "1986",
 title        = "Efficient Model Checking in Fragments of the Propositional Mu-Calculus",
 booktitle    = "LICS'86",
 pages        = "267--278",
)
@inproceedings(Janin_Walukiewicz1996:mso_mucalulus,
 author       = "David Janin and Igor Walukiewicz",
 year         = "1996",
 title        = "On the Expressive Completeness of the Propositional mu-Calculus with Respect to Monadic Second Order Logic",
 booktitle    = "CONCUR'96",
 series       = "Lect.\spacefactor \@m Notes Comput.\spacefactor \@m Sci.\spacefactor \@m ",
 volume       = "1119",
 pages        = "263--277",
 doi          = "10.1007/3-540-61604-7\_60",
)
@inproceedings(Kaivola1995:multl,
 author       = "Roope Kaivola",
 year         = "1995",
 title        = "Axiomatising Linear Time Mu-calculus",
 booktitle    = "CONCUR'95",
 series       = "Lect.\spacefactor \@m Notes Comput.\spacefactor \@m Sci.\spacefactor \@m ",
 volume       = "962",
 pages        = "423--437",
 doi          = "10.1007/3-540-60218-6\_32",
)
@article(Kozen1983:mucalculus,
 author       = "Dexter Kozen",
 year         = "1983",
 title        = "Results on the Propositional $\mu $-Calculus",
 journal      = "Theoret.\spacefactor \@m Comput.\spacefactor \@m Sci.\spacefactor \@m ",
 volume       = "27",
 number       = "3",
 pages        = "333--–354",
 doi          = "10.1016/0304-3975(82)90125-6",
)
@inproceedings(Kupferman_Vardi1998:weak_tree,
 author       = "Orna Kupferman and Moshe Y. Vardi",
 year         = "1998",
 title        = "Weak Alternating Automata and Tree Automata Emptiness",
 booktitle    = "STOC'98",
 pages        = "224--233",
 doi          = "10.1145/276698.276748",
)
@article(Kupferman_Vardi2001:weak,
 author       = "Orna Kupferman and Moshe Y. Vardi",
 year         = "2001",
 title        = "Weak Alternating Automata Are Not that Weak",
 journal      = "ACM Trans.\spacefactor \@m Comput.\spacefactor \@m Log.\spacefactor \@m ",
 volume       = "2",
 number       = "3",
 pages        = "408--429",
 doi          = "10.1145/377978.377993",
)
@article(Kupferman_Vardi2005:linear_branching,
 author       = "Orna Kupferman and Moshe Y. Vardi",
 year         = "2005",
 title        = "From Linear Time to Branching Time",
 journal      = "ACM Trans.\spacefactor \@m Comput.\spacefactor \@m Log.\spacefactor \@m ",
 volume       = "6",
 number       = "2",
 pages        = "273--294",
 doi          = "10.1145/1055686.1055689",
)
@inproceedings(ICALP::Lenzi1996,
 author       = "Giacomo Lenzi",
 year         = "1996",
 title        = "A Hierarchy Theorem for the {$\mu $}-Calculus",
 booktitle    = "ICALP'96",
 series       = "Lect.\spacefactor \@m Notes Comput.\spacefactor \@m Sci.\spacefactor \@m ",
 volume       = "1099",
 pages        = "87--97",
 doi          = "10.1007/3-540-61440-0\_119",
)
@inproceedings(Mateescu:2002:LMC,
 author       = "Radu Mateescu",
 year         = "2002",
 title        = "Local Model-Checking of Modal Mu-Calculus on Acyclic Labeled Transition Systems",
 booktitle    = "TACAS'02",
 series       = "Lect.\spacefactor \@m Notes Comput.\spacefactor \@m Sci.\spacefactor \@m ",
 volume       = "2280",
 pages        = "281--295",
 doi          = "10.1007/3-540-46002-0\_20",
)
@article(Muller1987,
 author       = "David E. Muller and Paul E. Schupp",
 year         = "1987",
 title        = "Alternating Automata on Infinite Trees",
 journal      = "Theoret.\spacefactor \@m Comput.\spacefactor \@m Sci.\spacefactor \@m ",
 volume       = "54",
 number       = "2--3",
 pages        = "267--276",
 doi          = "10.1016/0304-3975(87)90133-2",
)
@inproceedings(Niwinski1986:mucalculus,
 author       = "Damian Niwi{\'n}ski",
 year         = "1986",
 title        = "On fixed-point clones",
 booktitle    = "ICALP'86",
 series       = "Lect.\spacefactor \@m Notes Comput.\spacefactor \@m Sci.\spacefactor \@m ",
 volume       = "226",
 pages        = "464--473",
 doi          = "10.1007/3-540-16761-7\_96",
)
@inproceedings(Niwinski1988:fixedpoints,
 author       = "Damian Niwi{\'n}ski",
 year         = "1988",
 title        = "Fixed points vs. infinite generation",
 booktitle    = "LICS'88",
 pages        = "402--409",
 doi          = "10.1109/LICS.1988.5137",
)
@inproceedings(Wal:comkap,
 author       = "Igor Walukiewicz",
 year         = "1995",
 title        = "Completeness of {K}ozen's Axiomatization of the Propositional $\mu $-Calculus",
 booktitle    = "LICS'95",
 pages        = "14--24",
 doi          = "10.1109/LICS.1995.523240",
)
@article(Wilke:2001,
 author       = "Thomas Wilke",
 year         = "2001",
 title        = "Alternating Tree Automata, Parity Games, and Modal $\mu $-Calculus",
 journal      = "Bull.\spacefactor \@m Soc.\spacefactor \@m Math.\spacefactor \@m Belg.\spacefactor \@m ",
 volume       = "8",
 number       = "2",
 pages        = "359--391",
)