Scholar LogoI sent a query to Lee Giles, the guru at Penn State behind CiteSeer (with Steve Lawrence, who is now at Google) asking him which search-related papers are the most cited. I was struck by the near parity between Page and Brin's original paper on Google and Jon Kleinberg's paper on Hubs and Authorities. Giles did a bit of fiddling with Google Scholar and responded:

For web related work these are well cited in the Google Scholar using the query “web”:

 PDF] The Semantic Web
T Berners-Lee, J Hendler, O Lassila - View as HTML - Cited by 1347
... May 17, 2001. The Semantic Web. A new form of Web content that is meaningful to
computers will unleash a revolution of new possibilities. ... Web: A Research Agenda. ...
Scientific American, 2001 - www-personal.si.umich.edu

 [PDF] The anatomy of a large-scale hypertextual Web search engine
S Brin, L Page - View as HTML - Cited by 1087
Abstract In this paper, we present Google, a prototype of a large-scale search
engine which makes heavy use of the structure present in hypertext. Google ...
Computer Networks and ISDN Systems, 1998 - kulturinformatik.uni-lueneburg.de - firstrate.co.nz - net.cs.pku.edu.cn - scalab.uc3m.es - all 69 versions   

However, this one can’t be ignored:

 [PDF] Authoritative sources in a hyperlinked environment
J Kleinberg… - Cited by 1059
Abstract. The network structure of a hyperlinked environment can be a rich
source of information about the content of the environment, provided we ...
Journal of the ACM, 1999 - portal.acm.org - nan.dhs.org - cs.cmu.edu - mathe.tu-freiberg.de - all 73 versions

 This book is the first to discuss the web in any detail:

 [PS] Modern Information Retrieval
R Baeza-Yates, B Ribeiro-Neto, R Baeza-Yates - View as HTML - Cited by 1198
Page 1. Modern Information Retrieval. Ricardo Baeza-Yates. Berthier Ribeiro-Neto.
ACM Press New York. ... 1.1.2 Information Retrieval at the Center of the Stage . . ...
Addision Wesley, 1999 - dcc.ufmg.br - sunsite.dcc.uchile.cl - sims.berkeley.edu - portal.acm.org - all 7 versions »

All worthy reads!