@unknown(Ariola-et-al,
 author       = "Z. M. Ariola and H. Herbelin and A. Sabry",
 year         = "2009",
 title        = "A type-theoretic foundation of delimited continuations",
 journal      = "Higher-Order and Symbolic Computation",
 volume       = "22",
 number       = "3",
 pages        = "233--273",
 url          = "http://dx.doi.org/10.1007/s10990-007-9006-0",
)
@unknown(BrunnlerHabilitation,
 author       = "K. Br{\"u}nnler",
 year         = "2010",
 title        = "Nested Sequents",
 howpublished = "Habilitation thesis",
 url          = "http://arxiv.org/abs/1004.1845",
)
@unknown(BuismanGoreTableaux07,
 author       = "L. {Buisman (Postniece)} and R. Gor{\'e}",
 year         = "2007",
 title        = "A cut-free sequent calculus for bi-intuitionistic logic",
 editor       = "N. Olivetti",
 booktitle    = "Proc.\ of 16th Int.\ Conf.\ on Automated Reasoning with Analytic Tableaux and Related Methods, TABLEAUX 2007 (Aix en Provence, July 2007)",
 series       = "Lect.\ Notes in Comput.\ Sci.",
 volume       = "4548",
 publisher    = "Springer",
 pages        = "90--106",
 url          = "http://dx.doi.org/10.1007/978-3-540-73099-6_9",
)
@unknown(Crolard,
 author       = "T. Crolard",
 year         = "2001",
 title        = "Subtractive logic",
 journal      = "Theor.\ Comput.\ Sci.",
 volume       = "254",
 number       = "1--2",
 pages        = "151--185",
 url          = "http://dx.doi.org/10.1016/S0304-3975(99)00124-3",
)
@unknown(CrolardJLC,
 author       = "T. Crolard",
 year         = "2004",
 title        = "A formulae-as-types interpretation of subtractive logic",
 journal      = "J.\ of Log.\ and Comput.",
 volume       = "14",
 number       = "4",
 pages        = "529--570",
 url          = "http://dx.doi.org/10.1093/logcom/14.4.529",
)
@unknown(CurienHerbelin,
 author       = "P.-L. Curien and H. Herbelin",
 year         = "2000",
 title        = "The duality of computation",
 booktitle    = "Proc.\ of 5th Int.\ Conf.\ on Functional Programming, ICFP '00 (Montreal, Sept.\ 2000)",
 publisher    = "ACM Press",
 pages        = "233--243",
 url          = "http://doi.acm.org/10.1145/351240.351262",
)
@unknown(GorePostnieceTiu,
 author       = "R. Gor{\'e} and L. Postniece and A. Tiu",
 year         = "2008",
 title        = "Cut-elimination and proof-search for bi-intuitionistic logic using nested sequents",
 editor       = "C. Areces and R. Goldblatt",
 booktitle    = "Advances in Modal Logic",
 volume       = "7",
 publisher    = "College Publications",
 pages        = "43--66",
 url          = "http://www.aiml.net/volumes/volume7/Gore-Postniece-Tiu.pdf",
)
@unknown(Lukowski,
 author       = "P. {\L }ukowski",
 year         = "1996",
 title        = "Modal interpretation of Heyting-Brouwer logic",
 journal      = "Bull.\ of Sect. of Logic",
 volume       = "25",
 number       = "2",
 pages        = "80--83",
 url          = "http://www.filozof.uni.lodz.pl/bulletin/pdf/25_2_3.pdf",
)
@unknown(Monteiro,
 author       = "C. Monteiro",
 year         = "2006",
 title        = "Caracteriza\c c\~oes sem\^anticas e dedutivas da l\'ogica bi-intuicionista",
 type         = "Master's thesis",
 school       = "Universidade de Tr\'as-os-Montes e Alto-Douro",
)
@unknown(Negri,
 author       = "S. Negri",
 year         = "2005",
 title        = "Proof analysis in modal logic",
 journal      = "J.\ of Philos.\ Logic",
 volume       = "34",
 number       = "5--6",
 pages        = "507--544",
 url          = "http://dx.doi.org/10.1007/s10992-005-2267-3",
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@unknown(PintoUustalu,
 author       = "L. Pinto and T. Uustalu",
 year         = "2009",
 title        = "Proof search and counter-model construction for bi-intuitionistic propositional logic with labelled sequents",
 editor       = "M. Giese and A. Waaler",
 booktitle    = "Proc.\ of 18th Int.\ Conf.\ on Automated Reasoning with Analytic Tableaux and Related Methods, TABLEAUX 2009 (Oslo, July 2009)",
 series       = "Lect.\ Notes in Artif.\ Intell.",
 volume       = "5607",
 publisher    = "Springer",
 pages        = "295--309",
 url          = "http://dx.doi.org/10.1007/978-3-642-02716-1_22",
)
@unknown(Postniece-deep-inference,
 author       = "L. Postniece",
 year         = "2009",
 title        = "Deep Inference in Bi-intuitionistic Logic",
 editor       = "H. Ono and M. Kanazawa and R. Queiroz",
 booktitle    = "Proc.\ of 16th Int.\ Wksh.\ on Logic, Language, Information and Computation, WoLLiC 2009 (Tokyo, June 2009)",
 series       = "Lect.\ Notes in Artif.\ Intell.",
 volume       = "5514",
 publisher    = "Springer",
 pages        = "320--334",
 url          = "http://dx.doi.org/10.1007/978-3-642-02261-6_26",
)
@unknown(Rauszer74,
 author       = "C. Rauszer",
 year         = "1974",
 title        = "A formalization of the propositional calculus of {H-B} logic",
 journal      = "Studia Logica",
 volume       = "33",
 number       = "1",
 pages        = "23--34",
 url          = "http://dx.doi.org/10.1007/bf02120864",
)
@unknown(Rauszer74semiboolean,
 author       = "C. Rauszer",
 year         = "1974",
 title        = "Semi-boolean algebras and their applications to intuitionistic logic with dual operators",
 journal      = "Fund. Math.",
 volume       = "83",
 pages        = "219--249",
 url          = "http://matwbn.icm.edu.pl/ksiazki/fm/fm83/fm83120.pdf",
)
@unknown(Rauszer77,
 author       = "C. Rauszer",
 year         = "1977",
 title        = "Applications of {K}ripke models to {H}eyting-{B}rouwer logic",
 journal      = "Studia Logica",
 volume       = "36",
 number       = "1--2",
 pages        = "61--71",
 url          = "http://dx.doi.org/10.1007/bf02121115",
)
@unknown(ReedPfenning,
 author       = "J. Reed and F. Pfenning",
 year         = "2009",
 title        = "Intuitionistic letcc via labelled deduction",
 journal      = "Electron. Notes in Theor. Comput. Sci.",
 volume       = "231",
 pages        = "91--111",
 url          = "http://dx.doi.org/10.1016/j.entcs.2009.02.031",
)
@unknown(Restall,
 author       = "G. Restall",
 year         = "1977",
 title        = "Extending intuitionistic logic with subtraction",
 howpublished = "Unpublished note",
 url          = "http://consequently.org/writing/extendingj/",
)