International Symposium on Methodologies for Intelligent Systems Charlotte, N.C., Raś, Z., & Zemankova, M. (1991). Methodologies for intelligent systems: 6th International Symposium, ISMIS '91, Charlotte, N.C., USA, October 16-19, 1991 : proceedings. Springer-Verlag.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)International Symposium on Methodologies for Intelligent Systems Charlotte, N.C., Zbigniew Raś, و Maria Zemankova. Methodologies for Intelligent Systems: 6th International Symposium, ISMIS '91, Charlotte, N.C., USA, October 16-19, 1991 : Proceedings. Berlin ; New York: Springer-Verlag, 1991.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)International Symposium on Methodologies for Intelligent Systems Charlotte, N.C., et al. Methodologies for Intelligent Systems: 6th International Symposium, ISMIS '91, Charlotte, N.C., USA, October 16-19, 1991 : Proceedings. Springer-Verlag, 1991.