O'Brien, A. P., Smartt, T., McGrath, S., & Gaelic League of London. (1923). Accounts, leaflets and correspondence between Art O'Brien and the Treasurer Tómas Smartt and Secretary Máire Ní Flanngaile of the Gaelic League of London with subjects including organisation of Gaelic League classes and meetings, and money owed to the Irish Self-Determination League of Great Britain by the Gaelic League.

O'Brien, Art Patrick, et al. Accounts, Leaflets and Correspondence Between Art O'Brien and the Treasurer Tómas Smartt and Secretary Máire Ní Flanngaile of the Gaelic League of London with Subjects Including Organisation of Gaelic League Classes and Meetings, and Money Owed to the Irish Self-Determination League of Great Britain by the Gaelic League. 1923.