Hugh Thurston (1996). Early Astronomy. Springer. p. 188. ISBN0-387-94822-8. «Not only did Aryabhata believe that the earth rotates, but there are glimmerings in his system (and other similar systems) of a possible underlying theory in which the earth (and the planets) orbits the sun, rather than the sun orbiting the earth. The evidence is that the basic planetary periods are relative to the sun.»
Gola, 5; p. 64 in The Aryabhatiya of Aryabhata: An Ancient Indian Work on Mathematics and Astronomy, translated by Walter Eugene Clark (University of Chicago Press, 1930; reprinted by Kessinger Publishing, 2006). "Half of the spheres of the Earth, the planets, and the asterisms is darkened by their shadows, and half, being turned toward the Sun, is light (being small or large) according to their size."
van der Waerden, B. L. (June 1987). «The Heliocentric System in Greek, Persian and Hindu Astronomy». Annals of the New York Academy of Sciences500: 525-545. Bibcode:1987NYASA.500..525V. doi:10.1111/j.1749-6632.1987.tb37224.x. «It is based on the assumption of epicycles and eccenters, so it is not heliocentric, but my hypothesis is that it was based on an originally heliocentric theory.»
Swerdlow, Noel (June 1973). «A Lost Monument of Indian Astronomy». Isis64 (2): 239-243. doi:10.1086/351088. «Such an interpretation, however, shows a complete misunderstanding of Indian planetary theory and is flatly contradicted by every word of Aryabhata's description.»
van der Waerden, B. L. (June 1987). «The Heliocentric System in Greek, Persian and Hindu Astronomy». Annals of the New York Academy of Sciences500: 525-545. Bibcode:1987NYASA.500..525V. doi:10.1111/j.1749-6632.1987.tb37224.x. «It is based on the assumption of epicycles and eccenters, so it is not heliocentric, but my hypothesis is that it was based on an originally heliocentric theory.»
