ISBN 978-961-6165-57-0 SOR 21 Rupnik V. and L. Bogataj (Editors): The 1st Symposium on Opera!onal Research, SOR'93. Proceedings. Ljubljana: Slovenian Society Informa!ka, Sec!on for Opera!onal Research, 1993, 310 pp. Rupnik V. and M. Bogataj (Editors): The 2nd Interna!onal Symposium on Opera!onal Research in Slovenia, SOR'94. Proceedings. Ljubljana: Slovenian Society Informa!ka, Sec!on for Opera!onal Research, 1994, 275 pp. Rupnik V. and M. Bogataj (Editors): The 3rd Interna!onal Symposium on Opera!onal Research in Slovenia, SOR'95. Proceedings. Ljubljana: Slovenian Society Informa!ka, Sec!on for Opera!onal Research, 1995, 175 pp. Rupnik V., L. Zadnik S!rn and S. Drobne (Editors.): The 4th Interna!onal Symposium on Opera!onal Research in Slovenia, SOR'97. Proceedings. Ljubljana: Slovenian Society Informa!ka, Sec!on for Opera!onal Research, 1997, 366 pp. ISBN 9616165054. Rupnik V., L. Zadnik S!rn and S. Drobne (Editors.): The 5th Interna!onal Symposium on Opera!onal Research SOR '99, Proceedings. Ljubljana: Slovenian Society Informa!ka, Sec!on for Opera!onal Research, 1999, 300 pp. ISBN 9616165089. Lenart L., L. Zadnik S!rn and S. Drobne (Editors.): The 6th Interna!onal Symposium on Opera!onal Research SOR '01, Proceedings. Ljubljana: Slovenian Society Informa!ka, Sec!on for Opera!onal Research, 2001, 403 pp. ISBN 9616165127. Zadnik S!rn L., M. Bas! and S. Drobne (Editors): The 7th Interna!onal Symposium on Opera!onal Research SOR’03, Proceedings. Ljubljana: Slovenian Society Informa!ka, Sec!on for Opera!onal Research, 2003, 424 pp. ISBN 9616165151. Zadnik S!rn L. and S. Drobne (Editors): The 8th Interna!onal Symposium on Opera!onal Research SOR’05, Proceedings. Ljubljana: Slovenian Society Informa!ka, Sec!on for Opera!onal Research, 2005, 426 pp. ISBN 9616165208. Zadnik S!rn L. and S. Drobne (Editors): The 9th Interna!onal Symposium on Opera!onal Research SOR’07, Proceedings. Ljubljana: Slovenian Society Informa!ka, Sec!on for Opera!onal Research, 2007, 460 pp. ISBN 9789616165259. Zadnik S!rn L., J. Žerovnik, S. Drobne and A. Lisec (Editors): The 10th Interna!onal Symposium on Opera!onal Research SOR’09, Proceedings. Ljubljana: Slovenian Society Informa!ka, Sec!on for Opera!onal Research, 2009, 604 pp. ISBN 9789616165303. Zadnik S!rn L., J. Žerovnik, J. Povh, S. Drobne and A. Lisec (Editors): The 11th Interna!onal Symposium on Opera!onal Research SOR'11, Proceedings. Ljubljana: Slovenian Society Informa!ka, Sec!on for Opera!onal Research, 2011, 358 pp. ISBN 9789616165358. Zadnik S!rn L., J. Žerovnik, J. Povh, S. Drobne and A. Lisec (Editors): The 12th Interna!onal Symposium on Opera!onal Research SOR'13, Proceedings. Ljubljana: Slovenian Society Informa!ka, Sec!on for Opera!onal Research, 2013, 390 pp. ISBN 9789616165402. Zadnik S!rn L., J. Žerovnik, M. Kljaji ! Borštnar, S. Drobne (Editors): The 13th Interna!onal Symposium on Opera!onal Research SOR'15, Proceedings. Ljubljana: Slovenian Society Informa!ka, Sec!on for Opera!onal Research, 2015, 559 pp. ISBN 9789616165457. Zadnik S!rn L., J. Žerovnik, M. Kljaji ! Borštnar, S. Drobne (Editors): The 14th Interna!onal Symposium on Opera!onal Research SOR'17, Proceedings. Ljubljana: Slovenian Society Informa!ka, Sec!on for Opera!onal Research, 2017, 567 pp. ISBN 9789616165501. Zadnik S!rn L., M. Kljaji ! Borštnar, J. Žerovnik, S. Drobne, J. Povh (Editors): The 15th Interna!onal Symposium on Opera!onal Research SOR'19, Proceedings. Ljubljana: Slovenian Society Informa!ka, Sec!on for Opera!onal Research, 2019, 618 pp. ISBN 9789616165556. S. Drobne á L. Zadnik Stirn á M. Kljajic Borstnar á J. Povh á J. Zerovnik