@incollection{greene08chapter,
 author = {Derek Greene and P\'{a}draig Cunningham and Rudolf Mayer},
 booktitle = {Machine Learning Techniques for Multimedia: Case Studies on Organization and Retrieval},
 chapter = {3},
 editor = {Matthieu Cord and P\'{a}draig Cunningham},
 pages = {51--90},
 pdf = {http://www.derekgreene.com/papers/greene08chapter.pdf},
 publisher = {Springer},
 title = {Unsupervised Learning and Clustering},
 year = {2008}
}