BARLOW, L. The Spider's Apprentice: how to use web search engines . Monash Information Services, 1997. Disponible en: http://www.monash.com/spidap.html (Consultado 4 julio 97). BELKIN, N.J.; CROFT, W.B. "Retrieval techniques". Annual Review of Information Science and Technology . 22, 109-146, 1987. BELKIN, N.J. et al. "Combining the evidence of multiple query representations for information retrieval". Information Processing and Management. 31(3) 431-448, 1995. CHEN, H. et al. "Internet browsing and searching: user evaluations of category map and concept space techniques". Journal of American Society for Information Science . 49(7) 582-603, 1998. CROFT, W.B. "What do people want from information retrieval?: the top 10 research issues for companies that use and sell IR systems". D-Lib Magazine . nov 1995. Disponible en: http://ciir.cs.umass.edu/info/people/staff/croft.html (Consultado 1 jun. 96). DESAI, B.C. "Supporting discovery in virtual libraries". Journal of the American Society for Information Science . 48(3) 190-204, 1997. ELLIS, D. Ford, N. "In search of the unknown user: indexing, hypertext and the world wide web". Journal of Documentation . 54(1) 28-47, 1998. FRAKES, W. B.; BAEZA YATES, R. Information retrieval: data structures and algorithms . Englewood Cliffs: Prentice Hall, 1992. ISBN 0134638379. HAHN, T.B. "Text retrieval online: historical perspective on web search engines". Bulletin of the American Society for Information Science . 7-10, april/may 1998. HAVERKAMP, D.S.; GAUCH, S. "Intelligent information agents: review and challenges for distributed information sources". Journal of the American for Information Science . 49(4) 304-311, 1998. KOSTER, M. "Robots in the Web: threat or threat?". ConneXions . 9(4), april 1995. Disponible en: http://info.webcrawler.com/mak/projects/robots/threat-or-treat.html (Consultado 7 enero 96). KING, D.W. "Some economic aspects of the Internet". Journal of the American Society for Information Science . 49(11) 990-1002, 1998. LYNCH, C. "Searching the Internet". Scientific American . marzo 1997. Disponible en: http://www.sciam.com/0397issue/0397intro.html (Consultado 14 mar. 98). NAHL, D. "Learning the Internet and the structure of information behavior". Journal of the American Society for Information Science . 49(11) 1017-1023, 1998. PASTOR SÁNCHEZ, J.A. "Limitaciones del WWW en el ámbito de la información documental". Information World en Español . 6(4) 11-13, 1997.