- Letter to Rupert D'Oyly Carte from Charles W. Matthews asking him to become a member of a committee formed to determine an appropriate form of public memorial for Sullivan, 1901.
- Letter to Helen Carte from Charles W. Matthews thanking her for her help with the unveiling of the Sullivan memorial at Victoria Embankment (London). With reprint of an article on the event, 1903.
- Letter sent to the County Hall on behalf of Herbert (Bertie) Sullivan requesting permission to place a wreath at the Sullivan memorial on the anniversary of his death, 1927.
- Letters sent to the London County Council asking for a permanent plaque to be added to the Sullivan memorial in the Savoy Gardens, 1930.