[22] Astrophysical Journal, 55, 406, 1922.
[23] Monthly Notices, 82, 133, 1922.
[24] Astronomical Journal, 28, 75, 1914.
[25] Mt. Wilson Contr., No. 297; Astrophysical Journal, 62, 168, 1925.
[26] The latest and most reliable results bearing on the distribution of faint (hence apparently distant) nebulae are found in Seares’s revision and discussion of the counts made by Fath on plates of the Selected Areas with the 60-inch reflector. When the influence of the cluster in Virgo is eliminated the density appears to be roughly uniform for all latitudes greater than about 25°.
[27] Monthly Notices, 78, 3, 1917.
[28] Haas, Introduction to Theoretical Physics, 2, 373, 1925.
Transcriber’s Notes
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https://hdl.handle.net/2027/uc1.b3805680 (see pg 353). - The outline “CLASSIFICATION OF NEBULAE” starting on [page 3] lists N.G.C. 2117 as a type E7 nebula. The version of this paper printed in Contributions from the Mount Wilson Observatory No. 324 lists N.G.C 3115. Otherwise the papers are essentially identical.