Bán István: Mathematical exploration of the enviroment (1996)
Special thanks to the Company for Processing and Trading of Wood and Wooden Industrial Products (ÉRDÉRT) Hungarian Game Management and Trading Company Limited (MAVAD) Ipoly Forestry Share Company Kiskunság Forestry Share Company Man for Forest Foundation Mátra-Nyugatbükk Forestry and Wood-processing Share Company Zala Forestry and Wood-processing Share Company for their help in the publication of this study.