APA (7th ed.) Citation

Beattie, B. (2006). The Antipope who wasn't there: Three Formal Submissions to Pope John XXII.

Chicago Style (17th ed.) Citation

Beattie, Blake. The Antipope Who Wasn't There: Three Formal Submissions to Pope John XXII. 2006.

MLA (9th ed.) Citation

Beattie, Blake. The Antipope Who Wasn't There: Three Formal Submissions to Pope John XXII. 2006.

Warning: These citations may not always be 100% accurate.