Alfred W. Pollard. Sir Phillip Sidney's Astrophel & Stella. London: David Stott, 1888.
Berry, Edward. "The Poet as Warrior." Studies in English Literature, 1500-1900, vol. 29, no. 1 (Winter, 1989), pp. 21-34.
Lehnhof, Kent R. "Profeminism in Philip Sidney's 'Apologie for Poetrie.'" Studies in English Literature, 1500-1900, vol. 48, no. 1 (Winter, 2008), pp. 23-43.
Hilliard, Stephen S. "Stephen Gosson and the Elizabethan Distrust of the Effects of Drama," English Literary Renaissance vol. 9, no. 2 (Spring 1979), pp 225-239.
Are you looking for criticism about the two men? Their beliefs? A comparison of their beliefs and writings? I am very familiar with Dr. Johnson, but I'd have to do some research to check what I remember about Sydney.
Dryden was pretty versatile. His poetry, like his plays had songs, melodies to the narrative, and his own style of expression. Dryden was especially skilled in satire and character. His heroic couplets are especially famous.
The Defence of Poesy study guide contains a biography of Philip Sidney, literature essays, quiz questions, major themes, characters, and a full summary and analysis.
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