1819-1892 1901- 1901-1991 1910-1970 20thcentury american americanpoetry authors biography charles criticismandinterpretationjackson criticismandinterpretationolson criticismandinterpretationwhitman historyandcriticism jackson literarycriticism literarystudies:general literarystudies:poetry literature poetics poetry poets socialaspects sociolinguistics unitedstates usa walt