Sieben, H.J. (2022) “Notes on Synodality in the First Millennium: How did the Councils Define their Relationship with the Pope and Vice Versa during the First Millennium?”, Estudios Eclesiásticos. Revista de investigación e información teológica y canónica, 97(380), pp. 217–225. doi:10.14422/ee.v97.i380.y2022.007.