John Harvey, revised by T. Ayers, Witney, Thomas (fl. 1292–1342), Oxford Dictionary of National Biography, Oxford University Press, 2004; online edition (subscription required). Retrieved 2020-02-29.
Audrey Erskine, Grandison, John (1292–1369), Oxford Dictionary of National Biography, Oxford University Press, 2004; online edition (subscription required). Retrieved 2020-02-29.
