References

• Kenneth Glyn Jones, 1991. Messier's Nebulae and Star Clusters. 2nd ed, Cambridge University Press, p. 322. [ADS: 1991mnsc.book.....J].

• John Ellard Gore, 1902a. Messier's Nebulae. The Observatory, Vol. 25, pp. 264-269 (07/1902) [ADS: 1902Obs....25..264G]. M1-M24.
• John Ellard Gore, 1902b. Messier's Nebulae. [Continued from p. 269.] The Observatory, Vol. 25, pp. 288-293 (08/1902) [ADS: 1902Obs....25..288G] M25-M63 (leaving out M40, M45, M48).
• John Ellard Gore, 1902c. Messier's Nebulae. [Continued from p. 293.] The Observatory, Vol. 25, pp. 321-326 (09/1902) [ADS: 1902Obs....25..321G] M64-M103 (leaving out M102).
• John Ellard Gore, 1904. Studies in Astronomy. Chatto & Windus, London. Notably, Ch. XX., Messier's Nebulae, pp. 215-245.