- Frankfurter Allgemeine Zeitung, 17 December 1968
- Neue Zürcher Zeitung, 17 December 1968
- New York times, 17 December 1968
- [London] Times, 18 December 1968 (according to Herder correspondence, below).
- Concilium (German, French, English, Dutch (Concilium: internationaal tijdschrift voor theologie 1969), Italian, Portuguese, and Spanish)
- "Freedom for theology." Herder correspondence: a monthly review of the Christian world 6, no. 2 (February 1969): 46-48.
- "Declaration of 1,360 Catholic theologians on the Freedom of Theology (1968)." Küng in conflict, ed. Leonard Swidler (Garden City, NY: Doubleday & Company, Inc. 1981), 26-30. Swidler does not give his source.
If the Declaration was published in an English issue of Concilium, I overlooked it.
I have also seen this same declaration attached to Zürich.
Some other as yet unverified possibilities:
- Catholic voice (25 December 1968): 5?
- National Catholic reporter (1 January 1969)?
Update: Thanks to Chris, below, I have added the reprint in Küng in conflict, ed. Leonard Swidler (above), and the following notes from Hans Küng, Disputed truth: Memoirs, trans. John Bowden (London and New York: Continuum International Publishing Group, 2008), pp. 46 ff.: "At the Concilium Foundation Meeting in Paris on 12 October 1968", Küng suggests to Congar, Rahner, and Schillebeeckx "a declaration 'On the Freedom of Theology'", which Küng drafts back in Tübingen and from there submits first to the three others and then to "all the section directors through the Concilium secretariat" (46). "Once all the editorial committee of Concilium—a group of around 40 theologians, men and women, from the most varied nations and theological disciplines—have accepted the declaration it appears . . . on 17 December 1968 in the Frankfurter Allgemeine Zeitung, the Neue Zürcher Zeitung, the New York Times and other papers. At the same time it is published in the various editions of Concilium (German, French, English, Dutch, Italian, Portuguese and Spanish) and the theologians of the world are asked to subscribe to it. A small miracle occurs: the declaration is signed by 1360 Catholic theologians from 53 countries and sent to the Foundation Board of the Papal Secretariat" (47-48). "Professor Joseph Ratzinger of Tübingen also signs and has never withdrawn his signature" (48).