1. Th. Förster, Naturwiss. 33 (1946) 166; Th. Förster, Ann Phys. (Leipzig) 2 (1948) 55; Th. Förster, Radiation Research Supplement 2 (1960) 326-339.
2. For a review, see D. Beljonne, C. Curutchet, G. Scholes, R.J. Silbey, J. Phys. Chem B 113 (2009) 6583.
3. A.S. Davydov, Theory of Molecular Excitons (translated by M. Kasha and M. Oppenheimer) McGraw-Hill, NY 1962; A.S. Davydov, Zh. Eksp. I Teor 18 (1948) 210.
4. D.S. McClure, Solid State Physics, edited by F. Seitz and D. Turnbull (Academic Press NY 1959) volume 8, p. 1.