| A decade of outreach at Donegal County Archives | Brennan, Niamh | Article in Journal | | 2011 |
| A decade of outreach at Donegal County Archives | Brennan, Niamh | Article in Journal | | 2011 |
| A political minefield : southern loyalists, the Irish Grants Committee and the British government, 1922-31 | Brennan, Niamh | Article in Journal | | 1997 |
| Building homes for the rural labourers of Donegal | Brennan, Niamh | Article in Journal | | 2000 |
| Compensating southern Irish loyalists after the Anglo-Irish treaty | Brennan, Niamh Mary | Thesis | | 1995 |
| Donegal County Archives and 1916 | Brennan, Niamh | Article in Journal | | 2016 |
| Gweedore Hotel Visitors' books, 1842-74 | Brennan, Niamh | Article in Journal | | 2022 |
| Letterkenny Workhouse, 1844-1923 | Brennan, Niamh | Article in Journal | | 2019 |
| Sources for local social history : records of the building of labourers' cottages in Donegal | Brennan, Niamh | Article in Journal | | 2000 |
| The Ballagh barracks riot of 1815 : an early tithe protest in co. Tipperary | Brennan, Niamh | Article in Book | | 1989 |
| The Ballagh barracks rioters | Brennan, Niamh | Article in Book | | 1991 |
| The Cochranes of Redcastle | Brennan, Niamh | Article in Journal | | 2008 |
| Tracing the roots of the landed gentry : the Croftons of Roscommon | Brennan, Niamh | Article in Journal | | 1999 |