There is an extensive body of popular and scholarly literature on ancient and recent graffiti. The INDIGO Graffiti Reference Database was created to collect much of this graffiti-related literature in one place. It also contains literature about street art because contemporary graffiti and street art are hard to disentangle, and their relationship and hierarchy depend upon the source one consults. The database is a product of the academic graffiti project INDIGO. This collection of references is made available in two forms: a closed-source Citavi database (the *.ctv6archive file); an open-source Zotero database either consultable online (reading only), or downloadable here as a Zotero RDF or BibTex file (*.rdf and *.bib, respectively) for import into Zotero or other reference managers.