I completed my 36th year of university teaching and retired in 2015. My research work was in differential and complex algebraic geometry. I taught classes in San Diego for AoPS (Art of Problem Solving) during 2017-18 (precalculus) and 2018-19 (calculus).

For better or for worse, I've authored textbooks on abstract algebra, linear algebra, an integrated course in multivariable calculus/analysis and linear algebra, and (freely downloadable here) differential geometry.

With thanks to Patty Wagner, Cameron Zahedi, Cameron Bjorklund, Justin Payan, and especially to Eric Lybrand, my lecturesâ€”flaws and allâ€”for my Multivariable Mathematics course at UGA can now be viewed on YouTube. This course is based on my text, *Multivariable Mathematics: Linear Algebra, Multivariable Calculus, and Manifolds*.

You can email me at shifrin (at) uga.edu with relevant questions.