At the time of Griffith's Valuation the Flanagan family held lands in the parish of Killaraght, barony of Boyle, leased from the King estate and in the parishes of Kilglass, barony of Ballintober North and Kilcooley, barony of Roscommon. Earlier, in 1802, McParlan described "Mr. O'Flannikin's estate at Killarrat" as being of prime quality. Rentals of some of these lands were offered for sale in the Encumbered Estates Court in 1851. In the 1870s the Woulfe Flanagan estate in county Roscommon was over 1550 acres as well as over 2000 acres in county Sligo and 800 acres in county Clare. In 1906 Stephen W. Flanagan was the owner of 33 acres of untenanted land and buildings valued at £10 at Lecarrow, barony of Tirerrill. The family later had an address in London.
- Encumbered Estates' Court Rentals (O'Brien), Flanagan, 16 December 1851, Vol 9, MRGS 39/004 (microfilm copy in NUIG) ; National Archives of Ireland
- Woulfe-Flanagan family papers. Acc.1192. ; National Archives of Ireland
- O’Loghlen Papers: includes records of Co Roscommon lands & diaries of John Woulfe Flanagan, his wife was an O'Loghlen. MSS 13,891-13,899, MSS 14,318-14,335; National Library of Ireland
Contemporary printed sources
- PARLIAMENTARY PAPERS. ''Return of owners of land of one acre and upwards, in the several counties .... in Ireland''. HC 1876, LXXX: 315 (Roscommon ) & Sligo (321)
- ''GRIFFITH'S VALUATION OF IRELAND'[Primary Valuation of Tenements]', 1850-1858. : Boyle Union 34 (Rathtermon), 52 (Drumdoe)
- LEWIS, Samuel. ''A Topographical Dictionary of Ireland''. London: S. Lewis & Co., 1837: Vol II 125
- ORDNANCE SURVEY NAME BOOKS, County Sligo: Vol I 486
- PARLIAMENTARY PAPERS. Return of Landowners the purchase of whose properties has been approved by Irish Land Commission. : (1889),16.
- HUSSEY DE BURGH, U. H. ''The Landowners of Ireland. An alphabetical list of the owners of estates of 500 acres or £500 valuation and upwards in Ireland''. Dublin: Hodges, Foster and Figgis, 1878. [available online at www.askaboutireland.ie] : 163.
- PARLIAMENTARY PAPERS. ''Return of Untenanted Lands in Rural Districts, Distinguishing Demesnes on Which There is a Mansion...'', HC 1906, c, 177: 389.
- McPARLAN, James. ''Statistical Survey of the county of Sligo'' (Dublin: Royal Dublin Society, 1802). : 9.
- BATEMAN, John. ''The great landowners of Great Britain and Ireland''. London: Harrison, 1883. : p.169
Modern printed sources
- ''Jnl. of the Irish Family History Society'': PARKINSON, Danny. The Woulfe Flanagan family of Roscommon and Dublin. XI (1995), 110-118
- PINE, L.G. (ed). ''Burke's Genealogical and Heraldic History of the Landed Gentry of Ireland''. 4th ed. London: Burke's Peerage, 1958.: 290.
- McTERNAN, John C. ''Sligo: the light of bygone days, Vol.I Houses of Sligo and associated families''. Sligo: Avena Publications, 2009. : 426-7 (Rathtermon)