For 10 points, identify this author of Sonnets to Orpheus and The Duino Elegies.
One work by this author consists of letters written to Franz Kappus at a military academy, and one poem by this author includes the lines "We cannot know his legendary head" and "you must change your life." In addition to writing Letters To a Young Poet and "Archaic Torso of Apollo," one collection by this author dedicated to Vera Knoop contains fifty-five poems addressed to a mythological figure who "performed his song," and another collection by this author takes its name from an Italian castle and begins, "Who, if I cried out, would hear me among the Angelic Orders?" For 10 points, identify this author of Sonnets to Orpheus and The Duino Elegies.
One work by this author consists of letters written to Franz Kappus at a military academy, and one poem by this author includes the lines "We cannot know his legendary head" and "you must change your life.
Rainer Maria Rilke