Erskine, R., John, E. T., Gillies, W., O'Brien, A. P., Collins, M., & Bairéad, S. (1919). Correspondence and copy correspondence of Art Ó Briain with Ruaraidh Arscaine is Mhairr, William Gillies and E.T. John (British Celtic nationalists) regarding attendance at meetings, relationship between Gaelic League and Scottish Comunn nan Gàidheal and holding of Celtic Congress, with two memos to Michael Collins.

Erskine, Ruaraidh, et al. Correspondence and Copy Correspondence of Art Ó Briain with Ruaraidh Arscaine Is Mhairr, William Gillies and E.T. John (British Celtic Nationalists) Regarding Attendance at Meetings, Relationship Between Gaelic League and Scottish Comunn Nan Gàidheal and Holding of Celtic Congress, with Two Memos to Michael Collins. 1919.