| 'Cumhaidh na cléire', a '98 poem from north Leitrim | Ó Mórdha, Séamus | Article in Journal | | 1958 |
| An anti-tithe speech in Irish | Ó Mórdha, Séamus | Article in Journal | | 1961 |
| An Ghaeilge i gcontae an Chabháin i gcontae Longphuirt agusi gcontae na hIarmhi san bhlain 1823 | Ó Mórdha, Séamus | Article in Journal | | 1962 |
| Arthur Bennett's correspondence with Robert S. MacAdam | Ó Mórdha, Séamus | Article in Journal | | 1957 |
| Charlotte Brooke, her background and achievement | Ó Mórdha, Séamus | Article in Journal | | 1986 |
| Eimhear MacMahon Clogher's soldier-bishop | Ó Mórdha, Séamus | Article in Book | | 1940 |
| Fiachra Mac Brádaigh : poet and scribe of central Cavan | Ó Mórdha, Séamus | Article in Journal | | 1980 |
| Giolla Bríde Ó hEósa agus a shaothar | Ó Mórdha, Séamus | Article in Journal | | 1964 |
| Glangelvin's Irish College : Ardscoil Bhreifne | Ó Mórdha, Séamus | Article in Journal | | 1991 |
| Glangevlin's Irish college : Ardscoil Bhréifne, part 1 | Ó Mórdha, Séamus | Article in Journal | | 1989 |
| Lámhscríbhinní Gaeilge i gColáiste Phádraig | Ó Mórdha, Séamus | Article in Journal | | 1961 |
| Manuscript and scribal traditions in Meath | Ó Mórdha, Séamus | Article in Journal | | 2004 |
| Robert S. MacAdam's Louth correspondents (1831-1845) | Ó Mórdha, Séamus | Article in Journal | | 1958 |
| Ross MacCabe and some of his contemporaries | Ó Mórdha, Séamus | Article in Journal | | 1984 |
| Simon Macken : Fermanagh scribe and schoolmaster | Ó Mórdha, Séamus | Article in Journal | | 1959 |
| Some aspects of the literary tradition of the Breifne - Fermanagh area | Ó Mórdha, Séamus | Article in Journal | | 1983 |
| Tighearnach Chluain Eois | Ó Mórdha, Séamus | Article in Book | | 1940 |
| Údar 'Tórudiheacht na bhfíreun air Lorg Chríosda' | Ó Mórdha, Séamus | Article in Journal | | 1963 |
| Údar 'Tóruidheacht na bhfíreun air Lorg Chríosda' | Ó Mórdha, Séamus | Article in Journal | | 1963 |