Hannigan, B., O'Brien, A. P., Dutton, C. B., & Irish Freedom League. (1924). Correspondence of Art Ó Briain with Brian Hannigan,President of the Irish Freedom League, regarding Ó Briain’s refusal to attend a London-Irish conference, with correspondence between Hannigan and C. B. Dutton and an appeal to British trade unionists to support the Irish prisoners’ appeal cases.

Hannigan, Brian, et al. Correspondence of Art Ó Briain with Brian Hannigan,President of the Irish Freedom League, Regarding Ó Briain’s Refusal to Attend a London-Irish Conference, with Correspondence Between Hannigan and C. B. Dutton and an Appeal to British Trade Unionists to Support the Irish Prisoners’ Appeal Cases. 1924.