[10] "Pope John X," Catholic Encyclopedia. Accessed 2010.09.28.
[11] "Pope Leo VI," Catholic Encyclopedia. Accessed 2010.09.28.
[12] "Pope Stephen VII (VIII)," Catholic Encyclopedia. Accessed 2010.09.28. Note: Actual date of Pope Stephen VII's accession is either late 928 or early 929.
[13] "Pope Leo VIII," Catholic Encyclopedia. Accessed 2010.09.28.