People with Ph.D.s are not that frequently called Dr. Also, if there is one source that I am pretty sure would know how to refer to professors and Ph.D.s, it would be the Chronicle of Higher Education.
Chronicles of higher education might have a different publishing standard, but I'm not sure why they would.
This wikipedia entry seems to indicate that it is common to address someone of his stature as "Dr.", with the possible exception of perhaps in social settings where doing so might cause confusion (with MD).