[3] Monthly Notices R. A. S., 1919, 80, 104.
[4] Monthly Notices R. A. S., 1917, 77, 379.
[5] Astro-Physical Journal, 1917, 46, 249. Journ. Brit. Astron. Assoc., 1920, 30, 276.
[6] Monthly Notices, R. A. S., 1917, 77, 377.
[7] Amer. Journ. Sci., 34, 333.
[8] Monthly Notices, R. A. S., 1920, 80, 628.
[9] The Observatory 1920, April. From an Oxford Note Book.
[10] Monthly Notices, R. A. S., 1917. 78, 3 De Sitter, 1919, 80, 121, Jeans, 80, 146 Jeffreys.
[11] “Gravitation and the Principle of Relativity,” Eddington. Royal Institution of Great Britain, 1918.
[12] Journ. Brit. Astron. Assoc., 1920, 30, 125.