Goyal, Nitakshi, and Navpreet Singh Noorie. “θ-CLOSURE AND T\(_{{2}\frac{1}{2}}\) SPACES VIA IDEALS”. Italian Journal of Pure and Applied Mathematics, vol. 41, Feb. 2019, pp. 571-83, https://journals.uniurb.it/index.php/ijpam/article/view/7088.