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\bibitem{toldi85}
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\newblock {\em Velocity analysis without picking}.
\newblock PhD thesis, Stanford University, 1985.

\bibitem{Toldi89}
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\newblock Velocity analysis without picking.
\newblock {\em Geophysics}, 54(2):191--199, 1989.

\bibitem{lin:pick}
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\newblock Automatic picking and its applications.
\newblock {\em Stanford Exploration Project Report,
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\end{thebibliography}
