- Method for minimax optimization of power system operationValdma, Mati; Keel, Matti; Liik, Olev; Tammoja, Heiki2003 IEEE Bologna PowerTech : conference proceedings : 23-26 June, 2003, Faculty of Engineering, University of Bologna, Bologna, Italy. Vol. 42003 / [6] p. : ill https://ieeexplore.ieee.org/document/1304670