In O Pioneers!, Alexandra Bergson recalls "a poem she had liked in her schooldays after leaving Frank Shabata at the prison: 'Henceforth the world will only be/A wider prison-house to me.'" Lines 322-3 of the poem actually read: "And the whole earth would henceforth be/A wider prison unto me."
In Cather's story "A Resurrection," Martin Dempster asks Marjorie Pierson to recite the last four lines of "The Prisoner of Chillon."