Brill's New Pauly
- An authoritative encyclopedia covering all aspects of the classical world. This online version contains the complete 28 volume work published between 2002 and 2014.
Blackwell Reference Online
- A collection of reference works from Wiley-Blackwell, with good coverage of Classics topics.
Oxford Reference Online
- A collection of reference works published by Oxford University Press.
Cambridge Ancient History
- A 14-volume complete history of the ancient world through 600 AD.