| "Government sources said last night ..." : the development of the parliamentary press lobby in modern Ireland | Horgan, John, b. 1940 | Article in Book | University College Dublin Press | 2001 |
| 'The great war correspondent': Francis McCullagh, 1874-1956 | Horgan, John, b. 1940 | Article in Journal | | 2009 |
| Arms dumps and the IRA, 1923-32 | Horgan, John, b. 1940 | Article in Journal | | 1998 |
| Broadcasting and public life : RTE news and current affairs, 1926-1999 | Horgan, John, b. 1940 | Monograph or Collective Volume | Four Courts | 2004 |
| Churches, governments and the media : confronting their own and each other's responsibilities | Horgan, John, b. 1940 | Article in Book | | 2003 |
| Counterterrorism killings and Provisional IRA bombings, 1970-1998 | Gill, Paul ; Piazza, James A. ; Horgan, John | Article in Journal | | 2016 |
| Counterterrorism killings and Provisional IRA bombings, 1970-1998 | Gill, PaulHorgan, JohnPiazza, James A. | Article in Book | | 2017 |
| Divided we stand : the strategy and psychology of Ireland's dissident terrorists | Horgan, John, b. 1974 | Monograph or Collective Volume | Oxford University Press | 2013 |
| Fianna Fáil & arms decommissioning 1923-32 | Horgan, John, b. 1940 | Article in Journal | | 1997 |
| Great Irish reportage | | Monograph or Collective Volume | Penguin Ireland | 2013 |
| Here to Ssay? the rising threat of violent dissident republicanism in Northern Ireland | Horgan, John ; Morrison, John F. | Article in Journal | | 2011 |
| Irish foreign policy, Northern Ireland, neutrality and the Commonwealth : the historical roots of a current controversy | Horgan, John, b. 1940 | Article in Journal | | 1999 |
| Irish media : a critical history since 1922 | Horgan, John, b. 1940 | Monograph or Collective Volume | Routledge | 2001 |
| Journalism, Catholicism and anti-communism in an era of revolution. Francis McCullagh, war correspondent,1874-1956 | Horgan, John | Article in Journal | | 2009 |
| Journalists and Censorship : a case history of the NUJ in Ireland and the broadcasting ban 1971–94 | Horgan, John, b. 1940 | Article in Journal | | 2002 |
| Labour : the price of power | Horgan, John, b. 1940 | Monograph or Collective Volume | Gill & Macmillan | 1986 |
| Mary Robinson : an independent voice | Horgan, John, b. 1940 | Monograph or Collective Volume | O'Brien Press | 1997 |
| Noel Browne passionate outsider | Horgan, John, b. 1940 | Monograph or Collective Volume | Gill & Macmillan | 2000 |
| O'Connell - the man | Horgan, John Joseph, 1881-1967 | Article in Book | | 1949 |
| Parnell to Pearse : some recollections and reflections ; with a biographical introduction by John Horgan | Horgan, John Joseph, 1881-1967 | Monograph or Collective Volume | University College Dublin | 2009 |
| Playing the ‘green card’ - financing the provisional IRA : part 2 | Horgan, John ; Taylor, Max | Article in Journal | | 2003 |
| Proceedings of the Irish republican army general army convention, December 1969 | Horgan, John ; Taylor, Max | Article in Journal | | 1997 |
| Proceedings of the Irish Republican Army General Army convention, December 1969 | Horgan, John, b. 1974Taylor, Maxwell | Article in Journal | | 1997 |
| Reloading the Armalite? victims and targets of violent dissident Irish Republicanism, 2007-2015 | Morrison, John F. ; Horgan, John | Article in Journal | | 2016 |
| Reloading the Armalite? Victims and targets of violent dissident Irish Republicanism, 2007-2015 | Horgan, JohnMorrison, John F. | Article in Book | | 2017 |
| Seán Lemass : a man in a hurry | Horgan, John, b. 1940 | Article in Book | | 1996 |
| Seán Lemass : the enigmatic patriot | Horgan, John, b. 1940 | Monograph or Collective Volume | Gill & Macmillan | 1997 |
| Seán Lemass, Taoiseach, 1959-1966 | Horgan, John, 1940- | Thesis | | 1997 |
| The changing of the guard at Middle Abbey Street, 1961-73 | Horgan, John | Article in Book | | 2012 |
| The complete grammar of anarchy, by members of the War Cabinet and their friends | Horgan, John | Monograph or Collective Volume | Maunsell | 1918 |
| The Furrow : navigating the rapids, 1950-77 | Horgan, John | Article in Book | | 2014 |
| The media and the state : television and the press 1949-99 | Horgan, John, b. 1940 | Article in Book | | 2000 |
| The Parnell literature | Horgan, John Joseph, 1881-1967 | Article in Journal | | 1946 |
| The port of Cork | Horgan, John Joseph, 1881-1967 | Article in Journal | | 1957 |
| The provisional Irish republican army : command and functional structure | Horgan, John ; Taylor, Max | Article in Journal | | 1997 |
| The rational foraging terrorist : analysing the distances travelled to commit terrorist violence | Gill, Paul ; Horgan, John ; Corner, Emily | Article in Journal | | 2019 |
| Who were the volunteers? the shifting sociological and operational profile of 1240 Provisional Irish Republican Army members | Gill, Paul ; Horgan, John | Article in Journal | | 2013 |
| Who were the volunteers? the shifting sociological and operational profile of 1240 Provisional Irish Republican Army members | Gill, Paul ; Horgan, John | Article in Journal | | 2013 |