UCD Digital LibraryGroup of IFS Army soldiers firing artillery on the Four Courts photograph, 28 June 1922
Hathi Trust Digital LibraryThe struggle of the Irish people. Address to the Congress of the United States book, January 1921
Decade of Centenaries timelineIreland’s Solemn League and Covenant: Anti-conscription protest form document, April 1918
RTE Century IrelandBetween armed rebellion and democratic revolution: the Irish Question in 1917 open_in_new article, 2017