National Portrait GalleryThe Mad Bull (James Craig, 1st Viscount Craigavon; Michael Collins) cartoon, 15 February 1922
Documents on Irish Foreign Policy Extract from statement by Michael Collins on Northern Ireland policy open_in_new document, 4 February 1922
Hathi Trust Digital LibraryThe struggle of the Irish people. Address to the Congress of the United States book, January 1921
RTE Century Ireland Ireland’s Opportunity? The First World War & 1916 open_in_new article, 2016