\begin{thebibliography}{And00}

\bibitem[And00]{Andaloro00}
P.~Andaloro.
\newblock On total stopping times under 3x+1 iteration.
\newblock {\em Fibonacci Quarterly}, 38:73--78, 2000.

\bibitem[dlH00]{LaHarpe00}
Pierre de~la Harpe.
\newblock {\em Topics in Geometric Group Theory}.
\newblock Chicago Lectures in Mathematics, 2000.

\bibitem[Gri80]{Grigorchuk80}
Rostislav~I. Grigorchuk.
\newblock Bernside's problem on periodic groups.
\newblock {\em Functional Anal. Appl.}, 14:41--43, 1980.

\bibitem[Kel99]{Keller99}
Timothy~P. Keller.
\newblock Finite cycles of certain periodically linear permutations.
\newblock {\em Missouri J. Math. Sci.}, 11(3):152--157, 1999.

\bibitem[Koh05]{Kohl05}
Stefan Kohl.
\newblock {\em {Restklassenweise affine Gruppen}}.
\newblock Dissertation, Universität Stuttgart, 2005.

\bibitem[Lag06]{Lagarias06}
Jeffrey~C. Lagarias.
\newblock 3x+1 problem annotated bibliography, 2006.
\newblock http://arxiv.org/abs/math.NT/0309224.

\bibitem[LN02]{GAPDoc}
Frank Lübeck and Max Neunhöffer.
\newblock {\em {GAPDoc (version 0.99)}}.
\newblock RWTH Aachen, 2002.
\newblock GAP package, available at
  http://www.math.rwth-aachen.de/~Frank.Luebeck.

\bibitem[Mih58]{Mihailova58}
K.~A. Mihailova.
\newblock The occurence problem for direct products of groups.
\newblock {\em Dokl. Acad. Nauk. SSSR}, 119:1103--1105, 1958.

\bibitem[ML87]{MatthewsLeigh87}
K.~R. Matthews and G.~M. Leigh.
\newblock A generalization of the {Syracuse} algorithm in {\(\GF{q}[x]\)}.
\newblock {\em J. Number Theory}, 25:274--278, 1987.

\bibitem[Soi02]{GRAPE}
Leonard Soicher.
\newblock {\em {GRAPE -- GRaph Algorithms using PErmutation groups (version
  4.1)}}.
\newblock Queen Mary, University of London, 2002.
\newblock GAP package, available at http://www.gap-system.org.

\end{thebibliography}
