Nielsen, Herluf. 1977. “J. R. S. Phillips: Aymer De Valence, Earl of Pembroke 1307-1324. Baronial Politics in the Time of Edward II. At the Clarendon Press, Oxford, 1972. 379 S. £ 6 1 2”. Historisk Tidsskrift 13 (januar). https://tidsskrift.dk/historisktidsskrift/article/view/51936.