Internet Encyclopedia of Philosophy: Diogenes Laertius Concise article on this ancient biographer. http://www.utm.edu/research/iep/d/dioglaer.htm

Wikipedia: Diogenes Laertius Article drawing on the 1911 Britannica. http://www.wikipedia.org/wiki/Diogenes_Laertius

Lives of the Philosophers Online text of C.D. Yonge's translation. http://classicpersuasion.org/pw/diogenes/

Notes on Diogenes Laertius A criticism of this author's reliability, based on his Life of Socrates. http://www.uvm.edu/~jbailly/courses/Socrates/Notes/diogenes.html

The Manuscripts of "The Lives and Opinions of Eminent Philosphers" Hicks' notes from his 1925 translation of this text. http://www.tertullian.org/rpearse/manuscripts/diogenes_laertius.htm

Ancient Greek Scientists: Alexander Polyhistor Short biography and list of the works attributed to this thinker. http://www.tmth.edu.gr/en/aet/3/4.html