Pickard, J. B. (1961). John Greenleaf Whittier: An introduction and interpretation. New York: Barnes & Noble.
Dyfyniad Arddull ChicagoPickard, John B. John Greenleaf Whittier: An Introduction and Interpretation. New York: Barnes & Noble, 1961.
Dyfyniad MLAPickard, John B. John Greenleaf Whittier: An Introduction and Interpretation. New York: Barnes & Noble, 1961.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.