- [S124] Brett, William Baliol, first Viscount Esher (1815–1899), Steve Hedley, (Oxford Dictionary of National Biography, Oxford University Press, 2004 [http://www.oxforddnb.com/view/article/3350, accessed 15 March 2009];).
- [S7] London, England, Births and Baptisms, 1813-1906, Ancestry.com, (online database linked to digital images of records from the London Metropolitan Archives and Guildhall Library, 2009;), baptism of William Baliol, son of Joseph George and Dorothy Brett of Sloane Street, Gent, 2 Sep 1815, Chelsea, Middlesex (Reliability: 3).
- [S104] 1871 Census Returns of England and Wales, General Register Office, (2 April 1871;), RG 10/1382 f.20 p.7 (Reliability: 3).
Heath Farm, Watford
Honble Sir William B. Brett, Head, Mar, 56, One of Her Majesty's Judges of the Court of Common Pleas at Westminster, Middlesex St Lukes, Chelsea
Eugenie Brett, Wife, Mar, 46, (Lady) wife of Sir W. Brett, France, Lyons
Eugenie V.A. Brett, Daur, Unm, 17, Unmarried, living at home, Middlesex Westminster
Eugene L.S. Brett, Son, Unm, 16, Scholar, Middlesex Westminster
Fanny Gurwood, Mother in Law, Widow, 65, Head of her own Family, France, Lyons
Adela M.R. Gurwood, Sister in Law, Unm, 36, Unmarried living at home, France Paris
George Duckworth, Butler, Unm, 35, Domestic Servant, Yorkshire Forton
Thomas Dodman, Coachman, Mar, 40, Domestic Servant, Norfolk Heltenham
James Dance, Footman, Unm, 22, Domestic Servant, Berkshire, Barewood
Ellen H. Hughman, Ladysmaid, Unm, 28, Domestic Servant, Norfolk, Harleston
Elizabeth Scott, Cook, Unm, 30, Domestic Servant, Essex, Brentwood
Carry Hollands, Housemaid, Unm, 18, Domestic Servant, Kent, Luddesdown
Mary Ann Dodman, Housemaid, Unm, 13, Domestic Servant, Sussex, Bradfields
- [S205] FreeBMD, (www.freebmd.org.uk;), marriages of William Baliol Brett and Eugenie Mayer share reference St Geo Han Sq 1 2, June quarter 1850 (Reliability: 2).