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Lemaître, G. (1927). “Un univers homogène de masse constante et de rayon croissant rendant compte de la vitesse radiale des nébuleuses extra-galactiques”. Annales de la Société Scientifique de Bruxelles A. 47: 49–59. Bibcode:1927ASSB...47...49L. Partially translated in Lemaître, G. (1931). “Expansion of the universe, A homogeneous universe of constant mass and increasing radius accounting for the radial velocity of extra-galactic nebulae”. Monthly Notices of the Royal Astronomical Society. 91 (5): 483–490. Bibcode:1931MNRAS..91..483L. doi:10.1093/mnras/91.5.483.
