1. Sydney Chapman, “Mass Attack on Earth’s Mysteries,” Popular Mechanics, 1955, 104: 107–112, 260, 262, 264, and 266.
2. Gregory A. Good, “Sydney Chapman,” American National Biography 4 (Oxford: Oxford University Press, 1999), 716.
3. T. G. Cowling, “Sydney Chapman, 1888–1970, Elected F. R. S. 1919,” Biographical Memoirs of Fellows of the Royal Society 17 (London: Royal Society, 1971), 54.
4. Sydney Chapman and P.J. Melotte, “Photographic magnitudes of 262 stars within 25’ of the North Pole., Monthly Notices of the Royal Astronomical Society, 1913, 74:40–49.
5. Arthur Schuster, “The Diurnal Variation of Terrestrial Magnetism, With an Appendix by H. Lamb. On the Currents Induced in a Spherical Conductor by Variation of an External Magnetic Potential,” Philosophical Transactions 180A (1889): 467–518; “On the Origin of Magnetic Storms,” Proceedings ofthe Royal Society of London 85 (1911): 44–50; and “Critical Examination of the Possible Causes of Terrestrial Magnetism,” Proceedings of the Physical Society of London 24 (1912): 121–137.