\providecommand{\bysame}{\leavevmode\hbox to3em{\hrulefill}\thinspace}
\begin{thebibliography}{1}

\bibitem{breuil-conrad-diamond-taylor}
C.~Breuil, B.~Conrad, F.~Diamond, and R.~Taylor, \emph{On the modularity of
  elliptic curves over \protect{$\Q$}, or {W}ild $3$-adic exercises},  (2000),
  \\\protect{\sf
  http://www.math.harvard.edu/HTML/Individuals/Richard\_Taylor.html}.

\bibitem{cremona-mazur}
J.\thinspace{}E. Cremona and B.~Mazur, \emph{Visualizing elements in the
  \protect{Shafarevich-Tate} group}, to appear in Experiment. Math.

\bibitem{wiles:cmi}
A.\thinspace{}J. Wiles, \emph{The {B}irch and {S}winnerton-{D}yer
  {C}onjecture},  (2000), \\\protect{\sf
  http://www.claymath.org/prize\_problems/birchsd.htm}.

\end{thebibliography}
