Lukáč, Michal, and Jaroslav Mihálik. “Data Envelopment Analysis – A Key to the Museums’ ‘Secret Chamber’ of Marketing?”. Communication Today 9, no. 2 (November 1, 2018): 106–117. Accessed April 19, 2026. https://communicationtoday.fmk.ucm.sk/index.php/ct/article/view/218.