Cita APA (7th ed.)
Duston, A., & Nesselrath, A. The invisible made invisible: Angels from the Vatican / Allen Duston, O. P., and Arnold Nesselrath.
Cita Chicago (17th ed.)
Duston, Allen, i Arnold Nesselrath. The Invisible Made Invisible: Angels from the Vatican / Allen Duston, O. P., and Arnold Nesselrath.
Cita MLA (9th ed.)
Duston, Allen, i Arnold Nesselrath. The Invisible Made Invisible: Angels from the Vatican / Allen Duston, O. P., and Arnold Nesselrath.
Atenció: Aquestes cites poden no estar 100% correctes.