The 12th Professor Aleksander Zelias International Conference on Modelling and Forecasting of Socio-Economic Phenomena. International Conference. The 12th Professor Aleksander Zelias International Conference on Modelling and Forecasting of Socio-Economic Phenomena : Conference Proceedings : May 8-11, 2018, Zakopane, Poland. 1st edition. Cracow : Foundation of the Cracow University of Economics, 2018. online 611 s. Socio-Economic Modelling and Forecasting, No. 1 (2018). ISBN 978-83-65907-20-2.