Source: Emiliano, Flickr (edited). Licence.

Summon is usually the best starting point for finding articles, books and dissertations. 

• video intro to Summon (4 mins) 
• collection of guides if you need help with particular Summon searches

You may also want to run supplementary searches in these databases:

• Art & Architecture Source
• Google Scholar: an alternative to Summon
  • info about using Scholar 
  • video intro to Scholar (3 mins)

For introductory articles:

• Grove Art Online

For women photographers:

• Women and Photography introductory essay from Oxford Art Online
• Women in Photography International
• Women Photograph: international database of female and non-binary documentary photographers. Primarily designed for those wanting to  hire a documentary photographer, but may be useful for research purposes too.