T. Honkela, A. Hyvärinen, and J. Väyrynen. A72. Helsinki University of Technology, Laboratory of Computer and Information Science, Espoo, Finland, (2003)
J. Väyrynen, L. Lindqvist, and T. Honkela. Proceedings of the International Joint Conference on Neural Networks (IJCNN 2007), page 1031--1036. Orlando, Florida, USA, (2007)
J. Väyrynen, and T. Honkela. Proceedings of AKRR'05, International and Interdisciplinary Conference on Adaptive Knowledge Representation and Reasoning, page 135--140. (2005)