Balbinus and Pupienus
Links
Decimus Caelius Calvinus Balbinus
http://www.roman-empire.net/decline/balbinus.html
Biography of the life and brief reign of the Roman Emperor Balbinus.
Pupienus and Balbinus
http://www.roman-emperors.org/pupi.htm
Overview of the lives and reigns of these two co-rulers of the Roman Empire.
Pupienus and Balbinus
http://en.wikipedia.org/wiki/Pupienus
Wikipedia article about the lives of these two Roman Emperors.
The History of the Decline and Fall of The Roman Empire - Vol 1 - Chapter VII Part II
From Edward Gibbon's "Decline and Fall of The Roman Empire," details the co-rule of the empire by Balbinus and Pupienus.