International Study Conference on Classification Research, Augsbourg, Allemagne, Gesellschaft für Klassifikation. Fachtagung, Dahlberg, I., & Perreault, J. M. (1982). Universal classification I: Subject analysis and ordering systems. INDEKS Verlag.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)International Study Conference on Classification Research, Augsbourg, Allemagne, Gesellschaft für Klassifikation. Fachtagung, Ingetraut Dahlberg, و Jean M. Perreault. Universal Classification I: Subject Analysis and Ordering Systems. Frankfurt: INDEKS Verlag, 1982.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)International Study Conference on Classification Research, Augsbourg, Allemagne, et al. Universal Classification I: Subject Analysis and Ordering Systems. INDEKS Verlag, 1982.