Nicene and Post-Nicene Fathers, Ser. II, Vol. XII:
The Letters and Sermons of Leo the Great.: Letter CXXI. andCXXII.

Letters CXXI. and CXXII.

The former to Marcian Augustus, and the other to Julian the Bishop.

Asking him for further inquiries and information about the proper date for Easter in 455; cf. Letter LXXXVIII. chap. 4, above.