O'Brien of Cahirmoyle Papers, 1707-1983 Collection-level description only O'Byrne papers, 1708-1847 1 items O'Connell FitzSimon of Glencullen Papers, 1670-1964 127 items O'Dea Photograph Collection 5496 items Odoardo Barri papers, 1878-1978 11 items O'Donel of Newport Papers 124 items O'Donovan Rossa Papers 9 items Offprints of literary works by Douglas Hyde, 1912-1930 5 items O'Hara of Annaghmore Papers, 1585-1967 229 items Oireachtas na Gaeilge papers - papers of An tOireachtas, 1939-1994 Collection-level description only Oldham Photograph Album I Collection-level description only Oldham Photograph Album II Collection-level description only O'Mullane Papers, 1922-1956 15 items Original manuscript of Francis Ledwidge's poem 'Thomas McDonagh' with related letter from Lord Dunsany to Donagh MacDonagh, 1916 & 1940 2 items Ormond Family Papers, 1530-1850 Collection-level description only Ormonde Papers (Additional), 1635-ca. 1940 126 items Orpen & Sweeney Solicitors Papers 1 items Our Own Place Photographic Project 792 items P. J. McCall and John McCall Papers 11 items P. J. Smyth Papers 11 items