Cobzaş, Ş. “Antiproximinal Sets in Banach Spaces of Continuous Functions”.
Anal. Numér. Théor. Approx.
5, no. 2 (August 1, 1976): 127–143. Accessed April 14, 2025.
https://ictp.acad.ro/jnaat/journal/article/view/1976-vol5-no2-art2
.