Edwards, Thomas Esq.

Henrietta Cavendish, only daughter and heir of John Holles, 1st Duke of Newcastle, was born 11 February 1693/4, married Edward Harley, 2nd Earl of Oxford and Earl Mortimer, on 31 Oct. 1713, and died 9 December 1755. Edward Harley, 2nd Earl of Oxford and the Earl of Mortimer, was born 2 June 1689 and died 16 June 1741.

From the description of Patent to recreate a dukedom of Newcastle on the marriage of Henrietta, daughter of the last Duke of Newcastle, with the son of Lord Oxford, ca. 1713. (Pennsylvania State University Libraries). WorldCat record id: 702682417