Evidence of Counterion Size Effect on the Stability of Columnar Phase of Ionic Liquid Crystals Based on Pyridinium Salts Derived from <i>N</i>-3,4,5-Tri(alkyloxy)-benzyl-4-pyridone... oleh Isabela Dumitru, Florentina L. Chiriac, Monica Ilis, Iuliana Pasuk, Doina Manaila-Maximean, Marin Micutz, Teodora Staicu, Viorel Cîrcu