Williams, George W. The Most Excellent and Lamentable Tragedie of Romeo and Juliet: A Critical Edition.
Durham: Duke UP, 1964.

Thesis: You might think that a "Critical Edition" might contain some criticism of the play, but actually a "Critical Edition" is one that accounts for all of variations among the copies of the play that were printed more-or-less during Shakespeare's time. Williams has studied all editions of Romeo and Juliet printed between 1597 and 1637, compared them, and created a text that he believes is faithful to Shakespeare's original intention. The book has seven parts: "Textual Introduction" (which tells the story of the various editions), the text of Romeo and Juliet, "Textual Notes," "Staging Notes" (all about the various stage directions), "Press Variants," "Emendation of Accidentals," and "Historical Collation of Early Editions."

Bottom Line: It is what it is.