|←Author Index: Le||Pope Leo IV
|Pope from April 10, 847 to July 17, 855.|
Works by Leo IV 
Works about Leo IV 
- “Pope St. Leo IV,” in Catholic Encyclopedia, 1913.
- “Leo (popes)/Leo IV” in Encyclopædia Britannica, (11th ed.), 1911.
|Works by this author published before January 1, 1923 are in the public domain worldwide because the author died at least 100 years ago. Translations or editions published later may be copyrighted. Posthumous works may be copyrighted based on how long they have been published in certain countries and areas.|