Levering, M., & O'Regan, C. (2019). The achievement of Hans Urs von Balthasar: An introduction to his trilogy. The Catholic University of America Press.

Levering, Matthew, and Cyril O'Regan. The Achievement of Hans Urs Von Balthasar: An Introduction to His Trilogy. Washington, D.C.: The Catholic University of America Press, 2019.

Levering, Matthew, and Cyril O'Regan. The Achievement of Hans Urs Von Balthasar: An Introduction to His Trilogy. The Catholic University of America Press, 2019.