Journal of Formalized Mathematics
Volume 13, 2001
University of Bialystok
Copyright (c) 2001 Association of Mizar Users

Grzegorz Bancerek
University of Bialystok, Shinshu University, Nagano

### Summary.

In the paper we show useful facts concerning reverse and inclusion functors and the restriction of functors. We also introduce a new notation for the intersection of categories and the isomorphism under arbitrary functors.

#### MML Identifier: YELLOW20

The terminology and notation used in this paper have been introduced in the following articles [13] [7] [20] [21] [22] [4] [5] [14] [3] [12] [8] [6] [15] [16] [11] [10] [2] [17] [18] [19] [9] [1]

#### Contents (PDF format)

1. Reverse Functors
2. Intersection of Categories
3. Subcategories
4. Inclusion Functors and Functor Restrictions
5. Isomorphisms under Arbitrary Functor

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