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2. Fricke, R.: Elliptische Funktionen und ihre Anwendungen, Vol. One, Teubner Verlag, Leipzig (1930) pp. 450?451
3. Iwasawa, K.: Lectures onp-adicL-functions, Annals of Math. Studies No. 74
4. Klein, F., Fricke, R.: Vorlesungen über die Theorie der elliptischen Modulfunktionen, Vol. Two, Johnson Reprint Corporation, New York, and Teubner Verlag, Stuttgart (1966), from the 1890 edition
5. Kubert, D.: A system of free generators for the universal even ordinary distribution onQ k /Z k , to appear.