1. C.F. Bohren, D.R. Huffman, Absorption of Light by Small Particles (Wiley, New York, 1983)
2. O. Wiener, Abh. Math. Phys. K1 Königl. Ges. 32, 509 (1912)
3. J.D. Jackson, Classical Electrodynamics (Wiley, New York, 1962)
4. H.M. Nussenzveig, Causality and Dispersion Relations (Academic Press, New York, 1972)
5. D.R. Smith, N. Kroll, Phys. Rev. Lett. 85, 2933 (2000)