"The music manuscripts included in this edition are held in the British Library Reference Division Department of Music and the Music Library."
Low reduction (reels 2-19)
Reel 1. The British Library music manuscript collection : a listing and guide to Part one and Part two of the Harvester Microfilm collection / compiled by Roger Bray. Brighton, England : Harvester Press Microform Publications.-- Catalogue of the manuscript music in the British Museum / by Augustus Hughes-Hughes. London : Printed by order of the Trustees, 1964-1966 (Reprint of the 1906-1909 ed.)