PORVAZNÍK, Ján - LJUDVIGOVÁ, Ivana. Súčasné problémy volebného systému a možnosti ich celostného riešenia. In Management challenges in the 21st century. international research conference. 9th International Research Conference : Management challenges in the 21st century: innovation and innovative processes in business, public administration and educational organizations: Bratislava, April 27, 2017. - Bratislava : Vysoká škola manažmentu, 2017. ISBN 978-80-89306-34-3, p. 54-61 CD-ROM.