His Holiness Pope Radislav I of Rome-Ruthenia, then as a younger layman, with the Right Reverend Bishop James Pollard Clark, who started him in priestly formation. Bishop Clark was Bishop of the Southern States in the Anglican Province of Christ the King.
Read more here: https://www.statopontificio.org/papal.html
See more also at:
(Russian) https://www.catholicate.org/2025/06/fides-petraque-i.html
(Italian) https://www.catholicate.org/2025/06/fides-petraque-costituzione-apostolica.html
(English) https://www.catholicate.org/2025/06/fides-petraque-apostolic-constitution.html
(From the Stephenian Archives, Pontifical Apostolic Library.)