Database Spektrum 2009:
Information Retrieval: Concepts and Practical Considerations for Teaching a
Rising Topic:
Daniel Blank, Norbert Fuhr, Andreas Henrich, Thomas Mandl, Thomas Roelleke, Hinrich Schuetze, Benno Stein.
article (pdf).
Springer link.
VLDB Journal 2008 paper: Roelleke/Wu/Wang/Azzam: Modelling Retrieval in a Probabilistic Relational Algebra with a new Operator: The relational Bayes.
Springerlink portal,
local download.