Stack, A., & O'Connor, R. (1919). Two circular letters to IRA brigade commandants, both written by Austin Stack, on the formation of outposts and on the collection of information, forwarded by Michael Collins to Rory O'Connor.

Stack, Austin, and Rory O'Connor. Two Circular Letters to IRA Brigade Commandants, Both Written by Austin Stack, on the Formation of Outposts and on the Collection of Information, Forwarded by Michael Collins to Rory O'Connor. 1919.