\begin{thebibliography}{10}
\providecommand{\url}[1]{\texttt{#1}}
\providecommand{\urlprefix}{URL }
\providecommand{\eprint}[2][]{\url{#2}}

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K.~G. Chetyrkin, J.~H. {K\"uhn}, A.~Kwiatkowski.
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\newblock Vacuum saturation hypothesis and qcd sum rules.
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\newblock {Implications of the ALEPH tau lepton decay data for perturbative and
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\bibitem{Chetyrkin:1980pr}
K.~G. Chetyrkin, A.~L. Kataev, F.~V. Tkachov.
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\bibitem{Martinelli:1994ty}
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\newblock The {${\cal O} (\alpha_s^3)$} corrections to {$\sigma_{\rm tot} (e^+
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\bibitem{SurSam91}
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\newblock {{Total hadronic cross-section in $e^+ e^- $ annihilation at the four
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\bibitem{Chetyrkin:1996sr}
K.~G. Chetyrkin.
\newblock {Correlator of the quark scalar currents and {$\Gamma_{\rm tot}(H\to
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\newblock \eprint{hep-ph/9608318}.

\bibitem{Kiyo:2009gb}
Y.~Kiyo, A.~Maier, P.~{Maierh\"ofer}, P.~Marquard.
\newblock Reconstruction of heavy quark current correlators at {${\cal
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\newblock \emph{Nucl. Phys.}, B823:269--287, 2009.
\newblock \eprint{arXiv:0907.2120}.

\bibitem{Baikov:2005rw}
P.~A. Baikov, K.~G. Chetyrkin, J.~H. {K\"uhn}.
\newblock {Scalar correlator at ${\cal O}(\alpha_s^4)$, Higgs decay into b-
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\newblock \emph{Phys. Rev. Lett.}, 96:012003, 2006.
\newblock \eprint{hep-ph/0511063}.

\bibitem{Baikov:2008jh}
P.~A. Baikov, K.~G. Chetyrkin, J.~H. {K\"uhn}.
\newblock {Order $\alpha^4_s$ {QCD} Corrections to $Z$ and $\tau$ Decays}.
\newblock \emph{Phys. Rev. Lett.}, 101:012002, 2008.
\newblock \eprint{arXiv:0801.1821}.

\bibitem{Gracey:2009da}
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\newblock {Three loop MSbar operator correlation functions for deep inelastic
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\newblock \emph{JHEP}, 04:127, 2009.
\newblock \eprint{arXiv:0903.4623}.

\bibitem{Chetyrkin:1997dh}
K.~G. Chetyrkin.
\newblock {Quark mass anomalous dimension to {${\cal O}(\alpha_s^4)$}}.
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\newblock \eprint{hep-ph/9703278}.

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\bibitem{Baikov:2006ai}
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\newblock {New four loop results in QCD}.
\newblock \emph{Nucl. Phys. Proc. Suppl.}, 160:76--79, 2006.

\bibitem{Chetyrkin:1979bj}
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\bibitem{Baikov:prel}
P.~Baikov, K.~Chetyrkin, J.~{K\"uhn}.
\newblock {u}npublished.

\bibitem{Gorishnii:1990zu}
S.~G. Gorishny, A.~L. Kataev, S.~A. Larin, L.~R. Surguladze.
\newblock {CORRECTED THREE LOOP QCD CORRECTION TO THE CORRELATOR OF THE QUARK
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\newblock \emph{Mod. Phys. Lett.}, A5:2703--2712, 1990.

\bibitem{Baikov:2009uw}
P.~A. Baikov, K.~G. Chetyrkin, J.~H. {K\"uhn}.
\newblock {R(s) and hadronic tau-Decays in Order $\alpha_s^4$: technical
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\newblock 2009.
\newblock \eprint{arXiv:0906.2987}.

\bibitem{Vladimirov:IRR:80}
A.~A. Vladimirov.
\newblock Method for computing renormalization group functions in dimensional
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\newblock \emph{Theor. Math. Phys.}, 43:417, 1980.

\bibitem{Chetyrkin:1984xa}
K.~G. Chetyrkin, V.~A. Smirnov.
\newblock {$R^*$ Operation Corrected}.
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\bibitem{vermaseren-form}
J.A.M.Vermaseren.
\newblock New features of \texttt{FORM}.

\bibitem{Gorishnii:1989gt}
S.~G. Gorishny, S.~A. Larin, L.~R. Surguladze, F.~V. Tkachov.
\newblock {MINCER: PROGRAM FOR MULTILOOP CALCULATIONS IN QUANTUM FIELD THEORY
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\newblock \emph{Comput. Phys. Commun.}, 55:381--408, 1989.

\bibitem{Larin:1991fz}
S.~A. Larin, F.~V. Tkachov, J.~A.~M. Vermaseren.
\newblock The \texttt{FORM} version of \texttt{MINCER}.
\newblock NIKHEF-H-91-18.

\bibitem{Chetyrkin:1981qh}
K.~G. Chetyrkin, F.~V. Tkachov.
\newblock Integration by parts: The algorithm to calculate beta functions in 4
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\newblock \emph{Nucl. Phys.}, B192:159--204, 1981.

\bibitem{Fiamberti:2009jw}
F.~Fiamberti, A.~Santambrogio, C.~Sieg.
\newblock {Five-loop anomalous dimension at critical wrapping order in N=4
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\newblock \emph{JHEP}, 03:103, 2010.
\newblock \eprint{arXiv:0908.0234}.

\bibitem{Baikov:2005nv}
P.~A. Baikov.
\newblock A practical criterion of irreducibility of multi-loop feynman
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\newblock \eprint{hep-ph/0507053}.

\bibitem{Baikov:2007zza}
P.~A. Baikov.
\newblock {Recurrence relations in the large space-time dimension limit}.
\newblock \emph{PoS}, RADCOR2007:022, 2007.

\bibitem{Baikov:tadpoles:96}
P.~A. Baikov.
\newblock Explicit solutions of the 3--loop vacuum integral recurrence
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\newblock \eprint{hep-ph/9603267}.

\bibitem{Baikov:1996cd}
P.~A. Baikov.
\newblock Explicit solutions of the n--loop vacuum integral recurrence
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\newblock 1996.
\newblock \eprint{hep-ph/9604254}.

\bibitem{Baikov:explit_solutions:97}
P.~A. Baikov.
\newblock Explicit solutions of the multi-loop integral recurrence relations
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\newblock \emph{Nucl. Instrum. Meth.}, A389:347--349, 1997.
\newblock \eprint{hep-ph/9611449}.

\bibitem{Baikov:2010hf}
P.~A. Baikov, K.~G. Chetyrkin.
\newblock {Four Loop Massless Propagators: an Algebraic Evaluation of All
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\newblock \emph{Nucl. Phys.}, B837:186--220, 2010.
\newblock \eprint{arXiv:1004.1153}.

\bibitem{Smirnov:2010hd}
A.~V. Smirnov, M.~Tentyukov.
\newblock {Four Loop Massless Propagators: a Numerical Evaluation of All Master
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\newblock \eprint{arXiv:1004.1149}.

\bibitem{Fliegner:2000uy}
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\newblock Parallelizing the symbolic manipulation program form. i: Workstation
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\newblock 2000.
\newblock \eprint{hep-ph/0007221}.

\bibitem{Tentyukov:2004hz}
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\newblock 2004.
\newblock \eprint{cs/0407066}.

\bibitem{Tentyukov:2006pr}
M.~Tentyukov, H.~M. Staudenmaier, J.~A.~M. Vermaseren.
\newblock {ParFORM: Recent development}.
\newblock \emph{Nucl. Instrum. Meth.}, A559:224--228, 2006.

\bibitem{Tentyukov:2007mu}
M.~Tentyukov, J.~A.~M. Vermaseren.
\newblock {The multithreaded version of FORM}.
\newblock 2007.
\newblock \eprint{hep-ph/0702279}.

\bibitem{qgraf}
P.~Nogueira.
\newblock Automatic feynman graph generation.
\newblock \emph{J. Comput. Phys.}, 105:279--289, 1993.

\bibitem{vanRitbergen:1997va}
T.~van Ritbergen, J.~A.~M. Vermaseren, S.~A. Larin.
\newblock {The four-loop beta function in quantum chromodynamics}.
\newblock \emph{Phys. Lett.}, B400:379--384, 1997.
\newblock \eprint{hep-ph/9701390}.

\bibitem{Czakon:2004bu}
M.~Czakon.
\newblock The four-loop qcd beta-function and anomalous dimensions.
\newblock \emph{Nucl. Phys.}, B710:485--498, 2005.
\newblock \eprint{hep-ph/0411261}.

\end{thebibliography}
