1. Structure and Mechanism in Organic Chemistry, Bell and Sons, Ltd., London, 1953, p. 249.
2. Über Kumulene VII
1
): Die Ultrarotspektren einiger Kumulene und Acetylenglykole
3. The Infra-red Spectra of Complex Molecules, John Wiley, New York, 2nd. Ed., 1958, p. 61.
4. Infra-red Absorption Spectroscopy, Holden-Day, Inc. San Francisco and Nankoda Company Ltd. Tokyo, 2nd. Ed., 1964, p. 28.