Anna Chapin: Makers of Song (New York, 1904).
William Chappell: Old English Popular Music, 2 vols. (London, 1893).
H. Holbrook Curtis, M. D.: Voice Building and Tone Placing (New York, 1896).
Henry T. Finck: Songs and Song Writers (New York, 1910).
Ffrangcon-Davies: The Singing of the Future (London, 1904).
Folk-Songs from Somerset, 5 vols. (London, 1904-8).
Harry Plunkett Greene: Interpretation in Song (New York, 1912).
Max Heinrich: Correct Principles of Classical Singing (Boston, 1910).
H. L. F. Helmholtz: The Study of Sensations of Tone (Trans. by A. J. Ellis, 1875).
W. J. Henderson: The Art of Singing (New York, 1906).