This first preprint, *Witt cancellation seen as a cancellation*, is on the Witt Cancellation Theorem, with extra information about the Witt Ring. It is joint work with Sunil Chebolu and Ján Mináč. The illustrations are by Matthew Teigen.

Here are the slides for my talk, “*Vertex-magic graphs*,” from June 11, 2011, at the spring meeting of the Northeastern Section of the Mathematical Association of America.