The shape of services to come: values-based reference service for the largely digital library Chris D.Ferguson,Charles Aa.Bunge
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Reference services and technical services : interactions in library practice
edited by Gordon Stevenson and Sally Stevenson
Haworth Press, 1984
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Unobtrusive data analysis of digital reference questions and service at the internet public library: an exploratory study
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Services to remote users: marketing the library's role
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Reference services in the virtual library Judy E.Myers
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