APA (7th ed.) Citation

Hartog, H. (1961). European music in the twentieth century. Penguin Books.

Chicago Style (17th ed.) Citation

Hartog, Howard. European Music in the Twentieth Century. Londres: Penguin Books, 1961.

MLA (9th ed.) Citation

Hartog, Howard. European Music in the Twentieth Century. Penguin Books, 1961.