Ronald John McNeill, 1911 Encyclopædia Britannica, Volume 7… (1911)
“ The elder son, George Augustus Frederick (1806–1856) , 6th Earl Cowper, married Anne Florence, daughter of Thomas Philip, earl de Grey; and this lady at her father’s death became suo jure baroness Lucas of Cradwell. Francis Thomas de Grey, 7th Earl Cowper (1834–1905) , in addition to the other family titles, became in 1871 10th Baron Dingwall in the peerage of Scotland, and 8th Baron Butler of Moore Park in the peerage of Ireland as heir-general of Thomas, earl of Ossory, son of the 1st duke of Ormonde ”
