[104] Nature, April 20, 1905.

[105] Astrophysical Journal, vol. 14 (1901), p. 258.

[106] Nature, August 22, 1907.

[107] Popular Astronomy, vol. 12 (1904), p. 679.

[108] Mars as an Abode of Life, p. 69.

[109] Ibid., p. 146.

[110] Worlds in the Making, p. 49.

[111] Worlds in the Making, p. 53.

[112] Denning, Telescopic Work for Starlight Evenings, p. 158.

[113] Ibid., p. 166.