1. Schneider, K. (2006a), “ALA TechSource | How OPACs suck. Part 1: relevance rank (or the lack of it)”, available at: www.techsource.ala.org/blog/2006/03/how‐opacs‐suck‐part‐1‐relevance‐rank‐or‐the‐lack‐of‐it.html.
2. Schneider, K. (2006b), “ALA TechSource | How OPACs suck. Part 2: the checklist of shame”, available at: www.techsource.ala.org/blog/2006/04/how‐opacs‐suck‐part‐2‐the‐checklist‐of‐shame.html.
3. Schneider, K. (2006c), “ALA TechSource | How OPACs suck. Part 3: the big picture”, available at: www.techsource.ala.org/blog/2006/05/how‐opacs‐suck‐part‐3‐the‐big‐picture.html.
4. Gospodnetic, O. and Hatcher, E. (2005), Lucene in Action, Manning Publications, Greenwich, CT.
5. Rappoport, A. (n.d.), “Faceted metadata search – search tools report”, available at: www.searchtools.com/info/faceted‐metadata.html.