APA (7th ed.) Citation

Fabricius, J. A. (1858). Joannes VIII. (al.IX.) Romanus Papa.

Chicago Style (17th ed.) Citation

Fabricius, Johann Albert. Joannes VIII. (al.IX.) Romanus Papa. 1858.

MLA (9th ed.) Citation

Fabricius, Johann Albert. Joannes VIII. (al.IX.) Romanus Papa. 1858.

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