Cassell, K. A., & Hiremath, U. (2006). Reference and information services in the 21st century: An introduction. Facet.
Chicago-viite (17. p.)Cassell, Kay Ann, ja Uma Hiremath. Reference and Information Services in the 21st Century: An Introduction. London: Facet, 2006.
MLA-viite (9. p.)Cassell, Kay Ann, ja Uma Hiremath. Reference and Information Services in the 21st Century: An Introduction. Facet, 2006.
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