Author: Dmitri Pavlov Format: MarkdownItexFixed codecogs, trying to see if xymatrix works.
<a href="https://ncatlab.org/nlab/revision/diff/torsor+with+structure+category/8">diff</a>, <a href="https://ncatlab.org/nlab/revision/torsor+with+structure+category/8">v8</a>, <a href="https://ncatlab.org/nlab/show/torsor+with+structure+category">current</a>