- NLW MSS 23440-23462.
- 1842-ca. 1955 /
Correspondence and papers, 1842-c. 1955, of poet and socialist Robert Jones Derfel and including letters and cards, c. 1852-1905, from various correspondents; poetry and sermons, 1842-1913; scrapbooks, 1855-1905, containing material relating to Welsh socialism, etc.; books and pamphlets; and research material, 1911-c. 1955, compiled by T. J. Roberts in the course of his study of Robert Jones Derfel.
Derfel, R. J. (Robert Jones), 1824-1905.