Cropsey, Joseph, "Phaedo," Plato's World: Man's Place in the Cosmos, Chicago, IL: University of Chicago Press, 1995.

Excerpt:

Phaedo, so important by reason of its substance and occasion, receives its name from a historical figure about whom little can now be said to be known. Litle enough was remembered of him in later antiquity when Diogenes Laertius wrote his paragraph on Phaedo’s life: Socrates was helpful to Phaedo and Phaedo was a follower of Socrates.

Online:
Amazon
Google Books