S. Meshaik, T. Oner, “The maximal cardinality of the base in $P_{2}\times P_{2}$”, Sibirsk. Mat. Zh., 62:1 (2021), 144–153; Siberian Math. J., 62:1 (2021), 114–122
2001
2.
V. V. Rybakov, V. R. Kiyatkin, T. Oner, “Residual Finiteness for Admissible Inference Rules”, Algebra Logika, 40:5 (2001), 593–618; Algebra and Logic, 40:5 (2001), 334–347