Keller, T. J. (1958). Religious law in the decretals of Gregory IX: A general survey.
Lua i Stíl Chicago (17ú heag.)Keller, Thomas J. Religious Law in the Decretals of Gregory IX: A General Survey. 1958.
Lua MLA (8ú heag.)Keller, Thomas J. Religious Law in the Decretals of Gregory IX: A General Survey. 1958.
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