Lowther Castle, near Penrith, Cumberland
Writ of Gospatric.
Charters of Northern Houses, ed. D. A. Woodman (2012).
Catalogue of the sale of The Earl of Lonsdale's Collection, 6 parts, 15-17 April 1947 (furniture, paintings, prints, books, etc.).
Hugh Owen, The Lowther Family (Chichester, 1990).