Letters of Administration of the estate of the late Charles Blackwood, granted in favour of his mother, Emma Blackwood, upon his intestacy., 1867, MS.30014, folio 226. Papers of William Blackwood and Sons., MSS.30001-30984. National Library of Scotland Archives and Manuscripts Division. https://nlssb.as.atlas-sys.com/repositories/2/archival_objects/29349 Accessed September 24, 2024.