"Artstor is a nonprofit organization committed to enhancing scholarship and teaching 'through the use of digital images and media.'"
"Street Art Database is not only an online database of street-art. As the artists go to the streets to express their ideals, we go to the streets to help people better understanding urban art."
Los Angeles Magazine's list of articles about street art.

The Artist Who Chronicled the Bronx Graffiti Boom in the 1980s
‘I Have to Get That’: How Henry Chalfant Became a Graffiti Ambassador
History of graffiti and street art: the 1980s and the 1990s
How Basquiat and Street Artists Left Their Mark on Hip-Hop Culture
Snapping Back: The Street Art Spotters Immortalising Urban Art