\providecommand{\bysame}{\leavevmode\hbox to3em{\hrulefill}\thinspace}
\providecommand{\MR}{\relax\ifhmode\unskip\space\fi MR }
% \MRhref is called by the amsart/book/proc definition of \MR.
\providecommand{\MRhref}[2]{%
  \href{http://www.ams.org/mathscinet-getitem?mr=#1}{#2}
}
\providecommand{\href}[2]{#2}
\begin{thebibliography}{ABMW14}

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Emil {Artin}, \emph{{Zur Isotopie zweidimensionaler Fl\"achen im $\mathbb
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\bysame, \emph{Finite type invariants of w-knotted objects {II}: Tangles, foams
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\bibitem[Yaj64]{Yajima}
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\bibitem[Yan69]{Yanagawa}
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\end{thebibliography}
