Henry Green 
Shakespeare and the Emblem Writers: An Exposition of their Similarities of Thought and Expression [PDF ebook] 

Few only are the remarks absolutely needed by way of introduction to a work which within itself sufficiently explains and carries out a new method of illustration for the dramas of Shakespeare. This book is the results of genuine study. The results arrived at, though imperfect, are also grounded on real similitudes between Shakespeare and his predecessors and contemporaries; and those similitudes, parallelisms, or adaptations of thought, by whichever name distinguished, often arose from the actual impression made on his mind and memory by the Emblematists whose works he had seen, read, and used.