\begin{thebibliography}{1}

\bibitem{MRW09}
S.~M{\"u}ller, H.~C. Williams, and E.~Roettger, A cubic extension of the
  {{L}}ucas functions, {\em Ann. Sci. Math. Qu{\'{e}}bec} {\bf 33}(2) (2009),
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\bibitem{Roe09}
E.~Roettger, {\em A Cubic Extension of the {L}ucas Functions}, PhD thesis,
  University of Calgary, 2009.
\newblock available online at {\tt http://people.ucalgary.ca/$\sim$williams/}.

\bibitem{RWG13}
E.~L. Roettger, H.~C. Williams, and R.K. Guy, Some extensions of the {L}ucas
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\newblock In {\em Number {T}heory and {R}elated {F}ields}, pp.  279--319.
  Springer, 2013.

\bibitem{williams}
H.~C. Williams, {\em {{\'{E}}}douard {L}ucas and Primality Testing},
  Wiley-Interscience, 1998.

\end{thebibliography}
