There are 1 book by Mary M. O'Callaghan on BookOrb. A strong starting point is The government shall be upon whose shoulder? (1999). The bibliography below is in publication order, with series grouped in reading order.
Standalone books
Frequently asked questions
How many books has Mary M. O'Callaghan written?
BookOrb lists 1 book by Mary M. O'Callaghan.
Where should I start with Mary M. O'Callaghan?
A good starting point is The government shall be upon whose shoulder? (1999).
What is the Mary M. O'Callaghan books in order list?
In publication order: 1. The government shall be upon whose shoulder? (1999).