Historic American Sheet Music (Duke University Library Digital Collections)The Historic American Sheet Music collection drawn from Duke University's David M. Rubenstein Rare Book & Manuscript Library offers users access to over 3,000 pieces of mid-19th- to early 20th-century American sheet music. According to the website, "the sheet music chosen for digital reproduction represents a wide variety of music types including bel canto [opera], minstrel songs, protest songs, sentimental songs, patriotic and political songs, plantation songs, Civil War songs, spirituals, dance music, songs from vaudeville and musicals, 'Tin pan alley' songs, and songs from World War I. The collection is particularly strong in antebellum Southern music, Confederate imprints, and Civil war songs. Also included are piano music of marches, variations, opera excerpts, and dance music, including waltzes, quadrilles, polkas, etc."