Alexander Leggatt 
Shakespeare’s Comedy of Love [PDF ebook] 

First published in 1987. This study removes some of the critical puzzles that Shakespeare’s comedies of love have posed in the past. The author shows that what distinguishes the comedies is not their similarity but their variety – the way in which each play is a new combination of essentially similar ingredients, so that, for example, the boy/girl changes in The Merchant of Venice are seen to have a quite different significance from those in As You Like It.