APA Style

Darwin, C., Huxley, S, J. (2003). The Origin of Species: by Means of Natural Selection or the Preservation of Favored Races in the Struggle for Life (Signet Classics Edition). New York, USA: New American Library.

MLA Style

Darwin, Charles., Huxley, Sir, Julian. "The Origin of Species: by Means of Natural Selection or the Preservation of Favored Races in the Struggle for Life". Signet Classics Edition New York, USA: New American Library, 2003. Printed Book.