Prof. Kohonen has made many contributions to the field of artificial neural networks, including the Learning Vector Quantization algorithm, fundamental theories of distributed associative memory and optimal associative mappings, the learning subspace method and novel algorithms for symbol processing like redundant hash addressing. He has published several books and over 300 peer-reviewed papers. His most famous contribution is the Self-Organizing Map (also known as the Kohonen map or Kohonen artificial neural networks, although Kohonen himself prefers SOM). Due to the popularity of the SOM algorithm in many research and in practical applications, Kohonen is often considered to be the most cited Finnish scientist. The current version of the SOM bibliography contains close to 8000 entries.