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 TITLE = {Abstract and concrete categories},
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@unpublished {SHRT,
 author={Ad{\'a}mek, Ji{\v{r}}{\'\i} and Herrlich, Horst and Rosick\'y, 
 Ji{\v{r}}{\'\i} and Tholen, Walter},
 title={On a Generalized Small-Object Argument for the Injective 
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@incollection {DGT,
 AUTHOR = {Dikranjan, Dikran and Giuli, Eraldo and Tholen, Walter},
 TITLE = {Closure operators. {I}{I}},
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 combinatorics (Prague, 1988)},
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 ADDRESS = {Teaneck, NJ},
 YEAR = {1989},
 MRCLASS = {18A32 (18A40 18B30 54B30 54D10)},
 MRNUMBER = {91e:18002},
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@book {DT,
 AUTHOR = {Dikranjan, Dikran and Tholen, Walter},
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 YEAR = {1995},
 PAGES = {xviii+358},
 ISBN = {0-7923-3772-7},
 MRCLASS = {18B30 (18-02 18A20)},
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}
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 YEAR = {1979/80},
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MRREVIEWER = {G. E. Strecker},
}
@incollection {I,
 AUTHOR = {Isbell, John R.},
 TITLE = {Epimorphisms and dominions},
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 PAGES = {232--246},
 PUBLISHER = {Springer},
 ADDRESS = {New York},
 YEAR = {1966},
 MRCLASS = {08.10 (18.00)},
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 TITLE = {Categorical algebraic properties. {A} compendium on
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MRREVIEWER = {Temple H. Fay},
}
@book {M,
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 MRCLASS = {18-02},
 MRNUMBER = {50 \#7275},
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}
@incollection {Sa,
 AUTHOR = {Salbany, Sergio},
 TITLE = {Reflective subcategories and closure operators},
 BOOKTITLE = {Categorical topology (Proc. Conf., Mannheim, 1975)},
 PAGES = {548--565. Lecture Notes in Math., Vol. 540},
 PUBLISHER = {Springer},
 ADDRESS = {Berlin},
 YEAR = {1976},
 MRCLASS = {54A99},
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}
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 AUTHOR = {Sobral, Manuela},
 TITLE = {Absolutely closed spaces and categories of algebras},
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 VOLUME = {47},
 YEAR = {1990},
 NUMBER = {4},
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}
@article {S1,
 AUTHOR = {Sousa, Lurdes},
 TITLE = {Orthogonality and closure operators},
 JOURNAL = {Cahiers Topologie G\'eom. Diff\'erentielle Cat\'eg.},
 FJOURNAL = {Cahiers de Topologie et G\'eom\'etrie Diff\'erentielle
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 YEAR = {1995},
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 MRNUMBER = {97c:18004},
 MRREVIEWER = {Walter Tholen},
}
@phdthesis {S2,
 author={Sousa, Lurdes},
 title={Reflective and orthogonal hulls},
 school={Universidade de Coimbra},
 year={1997},
}
@article {T,
 AUTHOR = {Tholen, Walter},
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 JOURNAL = {Math. Nachr.},
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 VOLUME = {114},
 YEAR = {1983},
 PAGES = {63--85},
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 MRCLASS = {18A32},
 MRNUMBER = {85i:18002},
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}
@article {TAR,
 AUTHOR = {Trnkov{\'a}, V{\v{e}}ra and Ad{\'a}mek, Ji{\v{r}}{\'\i} and 
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 TITLE = {Topological reflections revisited},
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 VOLUME = {108},
 YEAR = {1990},
 NUMBER = {3},
 PAGES = {605--612},
 ISSN = {0002-9939},
 CODEN = {PAMYAR},
 MRCLASS = {18B30 (18A40 54B30 54E15)},
 MRNUMBER = {90e:18004},
 MRREVIEWER = {Y. T. Rhineghost},
}