Sybesma-Knol, N. Enige volkenrechtelijke vragen rond de Nederlandse Taalunie, c1987: t.p. (Karel Wellens) cover (Katholieke Universiteit Nijmegen)

Resolutions and statements of the U.N. Security Council ... c1990: CIP t.p. (Karel C. Wellens)

Diversity in secondary rules and the unity of international law, 1995: CIP t.p. (K.C. Wellens)

Remedies against international organisations, 2002: CIP t.p. (Karel Wellens; Catholic Univ. of Nijmegen) data sht. (b. Jan. 20, 1947) galley (prof. of pub. intl. law and the law of intl. org.)

Evolving principles of international law, 2012: t.p. (Karel C. Wellens) p. xiii (born in Antwerp, 20 January 1947; Dr. iur., Law Faculty, Univ.of Antwerp, 1977; professor of int. law and int. orgs., Law Faculty, Univ.of Nijmegen, 1982-2011)