1. The Oxford Dictionary of Quotations, 2nd ed. pp. 126,197, 209, and 517. London: Oxford University Press, pages 126,197,209,517 (1956).
2. Mansfield P, Grannell PK (1975)Phys Rev B 12 3618.
3. Cannell DM (1993)George Green, Mathematician and Physicist 1793–1841. London: Athlone Press.
4. Zavoisky EK, Altshuler SA, Kozyrev BM (1944)Zhur Ekspt Theor Viz 10 121 (in Russian); see also Zavoisky, E (1965) J Phys USSR9: 211 and and Zavoisky, E (1946) J Phys USSR10, 170 and 197 (in English).
5. Purcell EM, Torrey HC, Pound RV (1946)Phys Rev 69 37.