O’Byrne, P. V., O'Brien, A. P., & McGrath, S. (1921). Correspondence of Art Ó Briain with ‘ROC’, ‘R’ and ‘G’, P.V. O’Byrne (London IRA) and Eilís Ní Bhroin about O’Byrne's relief claim, with related memoranda of Sean McGrath and a letter of introduction for J.B. Beggs of the Irish Republican Association of South Africa.

O’Byrne, P. V., et al. Correspondence of Art Ó Briain with ‘ROC’, ‘R’ and ‘G’, P.V. O’Byrne (London IRA) and Eilís Ní Bhroin About O’Byrne's Relief Claim, with Related Memoranda of Sean McGrath and a Letter of Introduction for J.B. Beggs of the Irish Republican Association of South Africa. 1921.