Timo Honkela defended his PhD thesis Self-Organizing Maps in Natural Language Processing on 12th of December, 1997, in Helsinki University of Technology. Due to the multidisciplinary nature of the work, he received PhD (in Finnish "Filosofian tohtori") rather than PhD (tech) (in Finnish "Tekniikan tohtori"). In the dinner (in Finnish "karonkka"), there were more than 60 guests including Dieter Merkl (opponent), Teuvo Kohonen (custos), Erkki Oja, Olli Simula, Catherine Bounsathip, Johanna Honkela, Unto Honkela, Kaisa Honkela, Jukka Honkela, Kari Honkela, Olli Honkela (later Olli Hongell), Krista Lagus, Samuel Kaski, Kristiina Kalleinen, Tapio Vailahti, Aapo Hyvärinen, Kirsti Lonka, Timo Sampolahti, Aarno Lehtola, Eero Hvönen, Heikki Hyötyniemi, Harri Valpola (then Harri Lappalainen), Ville Pulkki, Sini Maury, and Pentti Määttänen.
