References
Cohen, D. E.: Ends and free products of groups. Math. Z.114, 9–18 (1970).
Dehn, M.: Über unendliche diskontinuierliche Gruppen. Math. Ann.71, 116–144 (1911).
Dunwoody, M. J.: The ends of finitely generated groups. J. Algebra12, 339–344 (1969).
Fricke, R., Klein, F.: Vorlesungen über die Theorie der automorphen Funktionen. Leipzig-Berlin: Teubner 1926.
Karrass, A., Solitar, D.: Note on a theorem of Schreier. Proc. Amer. Math. Soc.8, 696–697 (1957).
——: The subgroups of a free product of two groups with an amalgamated subgroup. Trans. Amer. Math. Soc.150, 227–255 (1970).
Magnus, W.: Residually finite groups. Bull. Amer. Math. Soc.75, 305–316 (1969).
— Karrass, A., Solitar D.: Combinatirial group theory: Presentations of groups. Pure and Appl. Math., Vol. 13. New York: Interscience 1966.
Seifert, H., Threlfall, W.: Lehrbuch der Topologie. New York: Chelsea Publishing Company 1945.
Shenitzer, A.: Decomposition of a group with a single defining relation into a free product. Proc. Amer. Math. Soc.6, 237–279 (1955).
Stallings, J. R.: On torsion-free groups with infinitely many ends. Ann. of Math.88, 312–334 (1968).
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This research was done independently by Hoare and Karrass-Solitar and was supported in part by grants from the National Research Council of Canada, Grant #A5602 and Grant #A5614.
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Hoare, A.H.M., Karrass, A. & Solitar, D. Subgroups of finite index of Fuchsian groups. Math Z 120, 289–298 (1971). https://doi.org/10.1007/BF01109993
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DOI: https://doi.org/10.1007/BF01109993