APA
Wojtyla K. (. J. P. I., . (1979). Sign of Contradiction. New York: A Crossroad Book; The Seabury Press.
Chicago
Wojtyla Karol (Pope John Paul II), . 1979. Sign of Contradiction. New York: A Crossroad Book; The Seabury Press.
Harvard
Wojtyla K. (. J. P. I., . (1979). Sign of Contradiction. New York: A Crossroad Book; The Seabury Press.
MLA
Wojtyla Karol (Pope John Paul II), . Sign of Contradiction. New York: A Crossroad Book; The Seabury Press. 1979.
