Azione Romana
(Expressing surprise that Leo has not by now confirmed the acts of the Synod, and asking for a speedy confirmation.)
Confirmationem synodi Chalcedonensis a pontifice uti necessariam petit. Ejus constantiam in vindicandis canonibus et reprimenda novitate laudat.
Philip Schaff and Henry Wace (eds.), New York: Christian Literature Publishing Co., 1890-1900. Public domain: English translation first published 1885-1900 (Nicene and Post-Nicene Fathers, Second Series). Latin: Migne, Patrologia Latina (1844-1855), public domain; transcription from Corpus Corporum (University of Zurich).