@book{Hatcher2002,
  author    = {Hatcher, Allen},
  title     = {Algebraic Topology},
  publisher = {Cambridge University Press},
  year      = {2002},
  isbn      = {0-521-79540-0},
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}

@book{BH1999,
  author    = {Bridson, Martin R. and Haefliger, Andr{\'e}},
  title     = {Metric Spaces of Non-Positive Curvature},
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  publisher = {Springer-Verlag},
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@book{Ballmann1995,
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  note      = {With an appendix by Misha Brin}
}

@article{LiptonTarjan1979,
  author  = {Lipton, Richard J. and Tarjan, Robert Endre},
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@misc{Stark2025,
  author        = {Stark, Emily},
  title         = {Visual metrics on boundaries of hyperbolic spaces},
  year          = {2025},
  eprint        = {2506.10108},
  archivePrefix = {arXiv},
  primaryClass  = {math.GT},
  doi           = {10.48550/arXiv.2506.10108},
  url           = {https://arxiv.org/abs/2506.10108v1},
  note      = {\href{https://arxiv.org/abs/2506.10108v1}{arXiv:2506.10108v1}}
}

@misc{Wilton2011,
  author       = {Wilton, Henry},
  title        = {Non-positively curved cube complexes},
  year         = {2011},
  howpublished = {Lecture notes},
  note      = {Winter 2011; revised June 29, 2012; \href{https://www.dpmms.cam.ac.uk/~hjrw2/Notes/cubenotes.pdf}{Author PDF}},
  url          = {https://www.dpmms.cam.ac.uk/~hjrw2/Notes/cubenotes.pdf}
}

@misc{Cashen2023,
  author       = {Cashen, Christopher H.},
  title        = {Notes on {Coxeter} groups},
  year         = {2023},
  howpublished = {Lecture notes, University of Vienna},
  note      = {Version of October 31, 2023; \href{https://www.mat.univie.ac.at/~cashen/Notes_on_Coxeter_groups.pdf}{Author PDF}},
  url          = {https://www.mat.univie.ac.at/~cashen/Notes_on_Coxeter_groups.pdf}
}

@article{Toyoda2016,
  author        = {Toyoda, Tetsu},
  title         = {Fixed point property for a {CAT(0)} space which admits a proper cocompact group action},
  journal       = {Kodai Mathematical Journal},
  volume        = {39},
  number        = {1},
  pages         = {129--153},
  year          = {2016},
  doi           = {10.2996/kmj/1458651696},
  url           = {https://doi.org/10.2996/kmj/1458651696},
  eprint        = {1102.0729},
  archivePrefix = {arXiv},
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@article{AntoniukFriedgutLuczak2017,
  author        = {Antoniuk, Sylwia and Friedgut, Ehud and {\L}uczak, Tomasz},
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  journal       = {Groups, Geometry, and Dynamics},
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  number        = {3},
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  archivePrefix = {arXiv},
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  note      = {\href{https://doi.org/10.4171/GGD/417}{DOI}}
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@incollection{Gromov1987,
  author    = {Gromov, Mikhail},
  title     = {Hyperbolic groups},
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  booktitle = {Essays in Group Theory},
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@article{BradyCrisp2007,
  author  = {Brady, Noel and Crisp, John},
  title   = {{CAT}(0) and {CAT}(-1) dimensions of torsion free hyperbolic groups},
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  number  = {1},
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  year    = {2007},
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@article{Ollivier2004,
  author  = {Ollivier, Yann},
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  year    = {2004},
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@article{Gromov2003,
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@article{IzekiNayatani2005,
  author  = {Izeki, Hiroyasu and Nayatani, Shin},
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@incollection{Sturm2003,
  author    = {Sturm, Karl-Theodor},
  title     = {Probability measures on metric spaces of nonpositive curvature},
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  series    = {Contemporary Mathematics},
  volume    = {338},
  pages     = {357--390},
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@article{GigliNobili2021,
  author  = {Gigli, Nicola and Nobili, Francesco},
  title   = {A differential perspective on gradient flows on {CAT}($\kappa$)-spaces and applications},
  journal = {Journal of Geometric Analysis},
  volume  = {31},
  pages   = {11780--11818},
  year    = {2021},
  doi     = {10.1007/s12220-021-00701-5},
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@article{KleinerLeeb1997,
  author  = {Kleiner, Bruce and Leeb, Bernhard},
  title   = {Rigidity of quasi-isometries for symmetric spaces and {Euclidean} buildings},
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  volume  = {86},
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@article{RaussenSkau2010,
  author  = {Raussen, Martin and Skau, Christian},
  title   = {Interview with {Mikhail Gromov}},
  journal = {Notices of the American Mathematical Society},
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  pages   = {391--403},
  year    = {2010},
  url     = {https://www.ihes.fr/~gromov/wp-content/uploads/2018/08/rtx100300391p.pdf},
  note    = {Interview of May 18, 2009; \href{https://www.ihes.fr/~gromov/wp-content/uploads/2018/08/rtx100300391p.pdf}{Author-hosted PDF}}
}

@incollection{BaumslagMyasnikovShpilrain1999,
  author    = {Baumslag, Gilbert and Myasnikov, Alexei G. and Shpilrain, Vladimir},
  title     = {Open problems in combinatorial group theory},
  booktitle = {Groups, Languages and Geometry},
  series    = {Contemporary Mathematics},
  volume    = {250},
  pages     = {1--27},
  publisher = {American Mathematical Society},
  address   = {Providence, RI},
  year      = {1999},
  url       = {https://web.stevens.edu/algebraic/alexeim/Publications/All_files_new/Openproblem_final_40.pdf},
  note      = {\href{https://web.stevens.edu/algebraic/alexeim/Publications/All_files_new/Openproblem_final_40.pdf}{Author manuscript}}
}

@misc{DuchesneSimon2026,
  author        = {Duchesne, Bruno and Simon, Christopher-Lloyd},
  title         = {The variety of group actions on all algebraic real hyperbolic spaces},
  year          = {2026},
  eprint        = {2603.03863},
  archivePrefix = {arXiv},
  primaryClass  = {math.MG},
  doi           = {10.48550/arXiv.2603.03863},
  url           = {https://arxiv.org/abs/2603.03863v1},
  note          = {Version submitted March 4, 2026; \href{https://arxiv.org/abs/2603.03863v1}{arXiv:2603.03863v1}}
}

@article{OllivierWise2011,
  author  = {Ollivier, Yann and Wise, Daniel T.},
  title   = {Cubulating random groups at density less than {$1/6$}},
  journal = {Transactions of the American Mathematical Society},
  volume  = {363},
  number  = {9},
  pages   = {4701--4733},
  year    = {2011},
  doi     = {10.1090/S0002-9947-2011-05197-4},
  url     = {https://www.ams.org/tran/2011-363-09/S0002-9947-2011-05197-4/S0002-9947-2011-05197-4.pdf},
  note    = {\href{https://doi.org/10.1090/S0002-9947-2011-05197-4}{DOI}}
}

@article{IzekiKondoNayatani2012,
  author  = {Izeki, Hiroyasu and Kondo, Takefumi and Nayatani, Shin},
  title   = {{N}-step energy of maps and the fixed-point property of random groups},
  journal = {Groups, Geometry, and Dynamics},
  volume  = {6},
  number  = {4},
  pages   = {701--736},
  year    = {2012},
  doi     = {10.4171/GGD/171},
  url     = {https://ems.press/content/serial-article-files/29632},
  note    = {\href{https://doi.org/10.4171/GGD/171}{DOI}}
}