Reference:

Timo Honkela, Samuel Kaski, Krista Lagus, and Teuvo Kohonen. WEBSOM—self-organizing maps of document collections. In Proceedings of WSOM'97, Workshop on Self-Organizing Maps, Espoo, Finland, June 4-6, pages 310–315. Helsinki University of Technology, Neural Networks Research Centre, Espoo, Finland, 1997.

Suggested BibTeX entry:

@incollection{Honkela97wsom,
    address = {Espoo, Finland},
    author = {Timo Honkela and Samuel Kaski and Krista Lagus and Teuvo Kohonen},
    booktitle = {Proceedings of {WSOM}'97, Workshop on Self-Organizing Maps, Espoo, Finland, June 4-6},
    pages = {310-315},
    publisher = {Helsinki University of Technology, Neural Networks Research Centre},
    title = {{WEBSOM}---Self-Organizing Maps of Document Collections},
    year = {1997},
}