John Cassian, Abbot
- Biography.
- http://www.saintpatrickdc.org/ss/0723.htm#cass

The Ecole Glossary: John Cassian
- Short biography, by Karen Rae Keck.
- http://www2.evansville.edu/ecoleweb/glossary/johncas.html

Cassian, John
- Short biographical entry in the Columbia Encyclopedia.
- http://www.bartleby.com/65/ca/Cassian.html

Prolegomena
- Introduction to John Cassian and his writings, from the Nicene and Post-Nicene Fathers of the Christian Church, second series, vol. 11.
- http://www.osb.org/lectio/cassian/prolegom.html

Catholic Encyclopedia: John Cassian
- Article on the monk and ascetic writer, who attempted to convey the teaching and way of life of the desert fathers and mothers to the fledgling monastic movement in Gaul.
- http://www.newadvent.org/cathen/03404a.htm