International ACMSIGIR Conference on Research and Development in Information Retrieval Melbourne, Australia, Association for Computing Machinery. Special Interest Group on Information Retrieval, & Croft, W. B. (1998). SIGIR ninety-eight: Proceedings of the 21st annual International ACM SIGIR Conference on Research and Development in Information Retrieval, Melbourne, Australia, August 24-28, 1998. ACM Press.

International ACMSIGIR Conference on Research and Development in Information Retrieval Melbourne, Australia, Association for Computing Machinery. Special Interest Group on Information Retrieval, and W. Bruce Croft. SIGIR Ninety-eight: Proceedings of the 21st Annual International ACM SIGIR Conference on Research and Development in Information Retrieval, Melbourne, Australia, August 24-28, 1998. New York: ACM Press, 1998.

International ACMSIGIR Conference on Research and Development in Information Retrieval Melbourne, Australia, et al. SIGIR Ninety-eight: Proceedings of the 21st Annual International ACM SIGIR Conference on Research and Development in Information Retrieval, Melbourne, Australia, August 24-28, 1998. ACM Press, 1998.