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british-history.ac.uk
'Inquisitions Post Mortem'. John de Grey of Retherfeld, knight. Writ, 7 June, 49 Edward III. (i.e. 1375)... Bartholomew Grey, knight, his son, aged 28 years and more, is his heir. A. E. Stamp, J. B. W. Chapman, Cyril Flower, M. C. B. Dawes and L. C. Hector, 'Inquisitions Post Mortem, Edward III, File 245', in Calendar of Inquisitions Post Mortem: Volume 14, Edward III (London, 1952), pp. 129-143. British History Online http://www.british-history.ac.uk/inquis-post-mortem/vol14/pp129-143 [accessed 20 April 2020].