JSTOR has a number of developmental project services that enhance research capabilities.
Understanding Shakespeare is a collaborative project between JSTOR Labs and the Folger Shakespeare Library . It’s a research tool that allows students, educators and scholars to use the text of Shakespeare’s plays to quickly navigate into the scholarship written about them—line by line.
Users simply click next to any line of text in a play and relevant articles from the JSTOR archive immediately load.
Explore the collection here.
Here is an example from Richard III
There are 17 articles within JSTOR which quote the first line of the play. Click on the number and it will link to the articles.