Christina Scull and Wayne G. Hammond released their two-volume reference work in 2006.
Volume one contained an 800-page chronology of real events in the original edition.
The preface explicitly stated this was not a handbook for fictional lands or characters.
The entire new work occupies 2720 pages total after expanding from the original counts.
David Oberhelman called it undoubtedly a seminal if not the definitive reference work on the Professor.