These online dictionaries and encyclopedias are not specifically art-focused but may lead you to useful information or other resources.
Sometimes you need to learn about the life of a particular artist, designer, or photographer. Here are some resources that provide that kind of information.
Notable American Women: Completing the Twentieth Century
by
Notable American Women: the modern period: a biographical dictionary
by
When you start writing your paper, there are resources that can help, such as this book: Short Guide to Writing About Art (N7467 .B37). The Online Writing Lab at Purdue (OWL) gives guidelines and tips on formatting your papers and citations in APA and MLA styles.
