Ernst-Ulrich Gekeler. Local and Global Ramification Properties of Elliptic Curves. In B. Heinrich Matzat, Gert-Martin Greuel, Gerhard Hiss, editors, Algorithmic Algebra and Number Theory - Selected Papers From a Conference Held at the University of Heidelberg, Germany, October 1997. pages 49-64, Springer, 1997. [doi]
Abstract is missing.