Παραπομπή APA

Sparke, L. S., & Gallagher, J. S. (2000). Galaxies in the universe: An introduction. Cambridge University Press.

Παραπομπή Chicago Style

Sparke, Linda Siobhan, και John S. Gallagher. Galaxies in the Universe: An Introduction. New York: Cambridge University Press, 2000.

Παραπομπή MLA

Sparke, Linda Siobhan, και John S. Gallagher. Galaxies in the Universe: An Introduction. Cambridge University Press, 2000.