- The Canon Law Society of America
- The Medieval Academy of America
- The American Catholic Historical Association
- The American Society of Church History
- Archivist for Missionary Society of St. Paul the Apostle
- Contributor to encyclopedias
"The Obligations and Rights of Clerics" in New Commentary on the Code of Canon Law. New York/Mahwah: Paulist Press, 2000.
"The Canonical Contribution to English Law," Studia Canonica 33 (1999) 505-525.
"The Eastern Churches: Historical Background," The Jurist 51 (1991) 1-17.
"The Medieval Canon Law on Sanctuary with Particular Reference to England," Unico Ecclesiae servitio, ed. M. Theriault & J. Thorn. Ottawa: St. Paul University, 1991.
"Historical Notes: The Clergy and the Diocese," Clergy Procedural Handbook, ed. R. Calvo & N. Klinger. Washington: Canon Law Society of America, 1992.
"The Magistery and Theologians from the Apostolic Fathers to the Gregorian Reform," Chicago Studies 17 (1978) 173-197.
"Marriage and Celibacy of the Clergy the Discipline of the Western Church: An Historico-Canonical Synopsis," The Jurist 32 (1972) 14-38, 189-212.
"Co-Responsibility in the First Five Centuries: Presbyteral Colleges and the Election of Bishops," The Jurist 31 (1971) 14-53. Reprinted in Who Decides for the Church, ed. James Coriden. Hartford: Canon Law Society of America, 1971.