Dissatisfied with the problems of the geocentric system inherited from Claudius Ptolemy, Nicholas Copernicus began the change from geocentrism to heliocentrism. His eponymous system was expounded first in the Commentariolus (written about 1508 and circulated privately in manuscript form) and then more fully and finally in his book, De Revolutionibus Orbium Coelestium (On the Revolutions of the Celestial Orbs) published as he lay dying in 1543.
Cramer, John Dr.
"The Copernican System: A Detailed Synopsis,"
Oglethorpe Journal of Undergraduate Research:
1, Article 2.
Available at: http://digitalcommons.kennesaw.edu/ojur/vol5/iss1/2