Ibert, Jean-Claude. Antoine de Saint Exupéry. Paris: Éditions Universitaires, 1953.
Ibsen, Henrik. Four Plays. New York: Holt, Rinehart and Winston, 1970.
Illanes, José Luis. On the Theology of Work. Dublin and Chicago: Scepter Books, 1967.
Inciarte, Fernando. Eindeutigkeit und Variation. Fribourg: Verlag Karl Alber, 1973.
Inciarte, Fernando. Forma Formarum: Strukturmomente der Thomistischen Seinslehre im Ruckgriff auf Aristoteles. Fribourg: Verlag Karl Alber, 1970.
Inciarte, Fernando. El Reto del Positivismo Lógico. Madrid: Edicaciones Rialp, 1974.
Inciarte, Fernando. Transzendentale Einbildungskraft. Bonn: H. Bouvier, 1970.
Ingardia, Richard. Thomas Aquinas: International Bibliography 1977-1990. Bowling Green, Ohio: Bowling Green State University, The Philosophy Documentation Center, 1993.
Innocent III, Pope. On the Misery of the Human Condition (De Miseria Humane Conditionis). Edited by Donald R. Howard; translated by Mararet Mary Dietz. Indianapolis: Bobbs-Merrill, 1969.
Ivy, A. C., John F. Pick, and W. F. P. Phillips. Observations on Krebiozen in the Management of Cancer. Chicago: Henry Regnery Co., 1956.