MLA

Ernest Augustus, King of Hanover, 1771-1851. Catalogue of Music for H. R. H. The Duke of Cumberland's Private Band. Manuscript. Box 876. circa 1830. https://collections.library.yale.edu/catalog/10000251.

APA, 6th edition

Ernest Augustus, King of Hanover, 1771-1851. (["Box 876"])(circa 1830)[Catalogue of Music for H. R. H. The Duke of Cumberland's Private Band. Manuscript]. https://collections.library.yale.edu/catalog/10000251.