vol. 43, no. 2 (2023)

Self-coalition graphs
Teresa W. Haynes, Jason T. Hedetniemi, Stephen T. Hedetniemi, Alice A. McRae, Raghuveer Mohan
Opuscula Math. 43, no. 2 (2023), 173-183, https://doi.org/10.7494/OpMath.2023.43.2.173
Lower density operators. Φ<sub>f</sub> versus Φ<sub>d</sub>
Gertruda Ivanova, Elżbieta Wagner-Bojakowska, Władysław Wilczyński
Opuscula Math. 43, no. 2 (2023), 185-197, https://doi.org/10.7494/OpMath.2023.43.2.185