Identifying congruence subgroups of the modular group

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Congruence Subgroups of the Modular Group

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ژورنال

عنوان ژورنال: Proceedings of the American Mathematical Society

سال: 1996

ISSN: 0002-9939,1088-6826

DOI: 10.1090/s0002-9939-96-03496-x