\def\cprime{$'$} \begin{thebibliography}{10} \bibitem{albert:simple-permutat:} {\sc Albert, M.~H., and Atkinson, M.~D.} \newblock Simple permutations and pattern restricted permutations. \newblock {\em Discrete Math. 300}, 1-3 (2005), 1--15. \bibitem{albert:the-enumeration:} {\sc Albert, M.~H., Atkinson, M.~D., and Klazar, M.} \newblock The enumeration of simple permutations. \newblock {\em J. Integer Seq. 6}, 4 (2003), Article 03.4.4, 18 pp. (electronic). \bibitem{atkinson:restricted-perm:} {\sc Atkinson, M.~D.} \newblock Restricted permutations. \newblock {\em Discrete Math. 195}, 1-3 (1999), 27--38. \bibitem{babson:generalized-per:} {\sc Babson, E., and Steingr{\'{\i}}msson, E.} \newblock Generalized permutation patterns and a classification of the {M}ahonian statistics. \newblock {\em S\'em. Lothar. Combin. 44\/} (2000), Art. B44b, 18 pp. (electronic). \bibitem{bona:the-number-of-p:} {\sc B{\'o}na, M.} \newblock The number of permutations with exactly {$r$} {$132$}-subsequences is {$P$}-recursive in the size! \newblock {\em Adv. in Appl. Math. 18}, 4 (1997), 510--522. \bibitem{bona:permutations-wi:} {\sc B{\'o}na, M.} \newblock Permutations with one or two {$132$}-subsequences. \newblock {\em Discrete Math. 181}, 1-3 (1998), 267--274. \bibitem{brignall:simple-permutat:} {\sc Brignall, R., Huczynska, S., and Vatter, V.} \newblock Simple permutations and algebraic generating functions. \newblock \texttt{arXiv:math.CO/0606186}. \bibitem{brignall:simple-permutat:b} {\sc Brignall, R., Ru\v{s}kuc, N., and Vatter, V.} \newblock Simple permutations: decidability and unavoidable substructures. \newblock In preparation. \bibitem{claesson:counting-occurr:} {\sc Claesson, A., and Mansour, T.} \newblock Counting occurrences of a pattern of type $(1,2)$ or $(2,1)$ in permutations. \newblock {\em Adv. in Appl. Math. 29}, 2 (2002), 293--310. \bibitem{corteel:common-interval:} {\sc Corteel, S., Louchard, G., and Pemantle, R.} \newblock Common intervals of permutations. \newblock In {\em Mathematics and computer science. III}, Trends Math. Birkh\"auser, Basel, 2004, pp.~3--14. \bibitem{ehrenfeucht:the-theory-of-2:} {\sc Ehrenfeucht, A., Harju, T., and Rozenberg, G.} \newblock {\em The theory of {$2$}-structures}. \newblock World Scientific Publishing Co. Inc., River Edge, NJ, 1999. \bibitem{foldes:on-intervals-in:} {\sc F{\"o}ldes, S.} \newblock On intervals in relational structures. \newblock {\em Z. Math. Logik Grundlag. Math. 26}, 2 (1980), 97--101. \bibitem{fulmek:enumeration-of-:} {\sc Fulmek, M.} \newblock Enumeration of permutations containing a prescribed number of occurrences of a pattern of length three. \newblock {\em Adv. in Appl. Math. 30}, 4 (2003), 607--632. \bibitem{ille:indecomposable-:} {\sc Ille, P.} \newblock Indecomposable graphs. \newblock {\em Discrete Math. 173}, 1-3 (1997), 71--78. \bibitem{mansour:restricted-132-:} {\sc Mansour, T.} \newblock Restricted $132$-alternating permutations and {C}hebyshev polynomials. \newblock {\em Ann. Comb. 7}, 2 (2003), 201--227. \bibitem{mansour:counting-occurr:a} {\sc Mansour, T.} \newblock Counting occurrences of $132$ in an even permutation. \newblock {\em Int. J. Math. Math. Sci.}, 25-28 (2004), 1329--1341. \bibitem{mansour:counting-occurr:} {\sc Mansour, T., and Vainshtein, A.} \newblock Counting occurrences of $132$ in a permutation. \newblock {\em Adv. in Appl. Math. 28}, 2 (2002), 185--195. \bibitem{mansour:counting-occurr:b} {\sc Mansour, T., Yan, S. H.~F., and Yang, L. L.~M.} \newblock Counting occurrences of $231$ in an involution. \newblock {\em Discrete Math. 306}, 6 (2006), 564--572. \bibitem{noonan:the-number-of-p:} {\sc Noonan, J.} \newblock The number of permutations containing exactly one increasing subsequence of length three. \newblock {\em Discrete Math. 152}, 1-3 (1996), 307--313. \bibitem{noonan:the-enumeration:} {\sc Noonan, J., and Zeilberger, D.} \newblock The enumeration of permutations with a prescribed number of ``forbidden'' patterns. \newblock {\em Adv. in Appl. Math. 17}, 4 (1996), 381--407. \bibitem{sabidussi:graph-derivativ:} {\sc Sabidussi, G.} \newblock Graph derivatives. \newblock {\em Math. Z. 76\/} (1961), 385--401. \end{thebibliography}