The Use of Electronic Mail in Biomedical Communication
http://www.jamia.org/cgi/content/abstract/7/1/103
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  peer-reviewed

Costello, Richard, Anthony Shaw, Roz Cheetham and Robert J. Moots
Journal of the American Medical Informatics Association
2000

Abstract:

Publication in general medical journals stimulates more conventional than electronic mail. However, the content of e-mail may be of greater scientific relevance. Electronic mail can be encouraged without fear of diminishing the quality of the communications received.