Caplan, D. (2005). Questions of possibility: Contemporary poetry and poetic form. Oxford University Press.
Lua i Stíl Chicago (17ú heag.)Caplan, David. Questions of Possibility: Contemporary Poetry and Poetic Form. New York: Oxford University Press, 2005.
Lua MLA (9ú heag.)Caplan, David. Questions of Possibility: Contemporary Poetry and Poetic Form. Oxford University Press, 2005.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.