A 2-Categories Companion

  title={A 2-Categories Companion},
  author={Stephen Lack},
  journal={arXiv: Category Theory},
  • S. Lack
  • Published 19 February 2007
  • Mathematics, Philosophy
  • arXiv: Category Theory
This paper is a rather informal guide to some of the basic theory of 2-categories and bicategories, including notions of limit and colimit, 2-dimensional universal algebra, formal category theory, and nerves of bicategories. 

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