National Portrait Gallery
The Mad Bull (James Craig, 1st Viscount Craigavon; Michael Collins)
cartoon, 15 February 1922
Google Arts and Culture
Memorandum from Arthur Griffith to de Valera on Ulster
open_in_newdocument, 8 November 1921
National Archives UK
Cabinet Memorandum – Ireland (Draft Constitution)
open_in_newdocument, 1 June 1922
National Archives UK
Irish Settlement: Proposals of the British government
open_in_newdocument, 20 July 1921
National Archives UK
Letter from Sir James Craig to the Prime Minister
open_in_newdocument, 29 July 1921
National Archives UK
Letter from Lloyd George inviting Craig and de Valera to a conference
open_in_newdocument, 24 June 1921

Bicycles, Barracks & Bandoliers
Memo regarding Catholic recruitment in the RUC and USC
memo, March 1922
Google Arts and Culture
Instructions to Plenipotentiaries from Cabinet
open_in_newdocument, 7 October 1921
Houses of Oireachtas
Correspondence between de Valera and Lloyd George
open_in_newdebate, 14 September 1921
Hathi Trust Digital Library
The struggle of the Irish people. Address to the Congress of the United States
book, January 1921