31 Oct 1995 There is a survey of several diagram packages in the latest issue of TUGboat. Gabriel Valiente Feruglio Typesetting Commutative Diagrams TUGboat, volume 15 (1994), no. 4, 466-484 However, kuvio.tex and it's documentation has evolved quite substantially since this article appears to have been written; although not since vol. 15, no.4 arrived in my mailbox last week. :^. I have a few comments regarding this article. In the description of kuvio.tex on page 471, there is the following statement. "It supports diagonal arrows of different shapes and in many different, although not arbitrary, slopes ..." This is false, though the fault probably lies with the state of the documentation at the time - January 1995 according to the citation on page 473. That is, the slope of arrows is, in fact, arbitrary. Numerous features have been added to kuvio.tex since January 1995. Among these are *diagram types* (\newDiagram, \newFigure and \newGraph) and the *flexible grid* (\flexible), both of which I would use when typesetting a diagram like the one on page 475. Another big one is *diagram compilation*. The use of the *rigid grid* inherent in the \Diagram \endDiagram pair certainly affects the appearence of the square typeset on page 482. To see this, try typesetting the following two "squares". \def\A{A\times A\times A\times A} \Diagram \A & \rTo ^f & B \\ \dTo {g'} \\ C & \rTo _{f'} & D \\ \endDiagram \Dg \A & \rTo ^f & B \\ \dTo {g'} \\ C & \rTo _{f'} & D \\ \endDg It's still true that arrows don't stretch to match wide labels but I consider this a feature. :^) Anders ****************************************************************************** 26 Jan 1996 As of patchlevel 214, horizontal arrows are stretched to accomodate wide centered labels. (That is, the last sentence above no longer holds.)