Union List of Artist Names
The Union List of Artist Names (ULAN) is an online database containing the names, alternative names, and biographies of visual artists and architects. It also contains other information such their patrons, and the subjects of portraits they have created. The ULAN is run by the Getty Research Institute. The institute began developing the database in 1984. 
- Getty Research Institute. About the ULAN. Retrieved 19 February 2018.
- Breitman, Karin; Casanova, Marco Antonio; Truszkowski. Walt (2007). Semantic Web: Concepts, Technologies and Applications, pp. 246-247. Springer Science & Business Media. ISBN 184628581X