O'Brien, A. P. (1921). Correspondence between Art O'Brien and; "R.D", regarding the prohibition of the London I.R.A attending Gaelic League meetings during the War of Independence; Donncadh O'Céileacháin, concerning a fund-raising event; and to "M.R", mainly relating to providing relief for political prisoners in England through the Irish National Aid Fund.

O'Brien, Art Patrick. Correspondence Between Art O'Brien and; "R.D", Regarding the Prohibition of the London I.R.A Attending Gaelic League Meetings During the War of Independence; Donncadh O'Céileacháin, Concerning a Fund-raising Event; and to "M.R", Mainly Relating to Providing Relief for Political Prisoners in England Through the Irish National Aid Fund. 1921.