Twisk, Jos W.R.
Applied multilevel analysis: a practical guide
Cambridge University Press, 2006
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Lenk, John D.
Handbook of advanced troubleshooting
Prentice-Hall, 1983
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Bradley, Phil
The advanced internet searcher's handbook
Lawrence Erlbaum Associates, 1999
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Bradley, Phil
Advanced internet seacher's handbook
Library Association, 2002
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Bradley, Phil
The Advanced internet searcher's handbook
Facet Publishing, 2004
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