Kobbés complete opera book (10th ed.) / ed. and rev. by the earl of Harewood.

MLA

Harewood, George Lascelles, and Gustave Kobbé. Kobbés Complete Opera Book (10th Ed.) / Ed. and Rev. by the Earl of Harewood. London, 1987.

APA

Harewood, G. Lascelles, & Kobbé, G. (1987). Kobbés complete opera book (10th ed.) / ed. and rev. by the earl of Harewood. London.

Chicago

Harewood, George Lascelles, and Gustave Kobbé. Kobbés Complete Opera Book (10th Ed.) / Ed. and Rev. by the Earl of Harewood. London, 1987.