- FondsBeaton - Papers of Sir Cecil Beaton
- SeriesA - Correspondence
- SubseriesA1 - General letters to Beaton
- File57 - Martha Bibescu. Letters to Beaton.
- Item1 - Autograph letter signed to Miss Hose, from London
- Item2 - Typescript letter signed to Miss Hose, from Cornwall
- Item3 - Autograph letter signed to Beaton, from London