- Ernesto Barrientos, Sergio Mendoza, Pablo Padilla. Extending Friedmann Equations Using Fractional Derivatives Using a Last Step Modification Technique: The Case of a Matter Dominated Accelerated Expanding Universe. Symmetry, 13(2):174, 2021.
- Askhat I. Diveev, Elizaveta Yu. Shmalko. Research of Trajectory Optimization Approaches in Synthesized Optimal Control. Symmetry, 13(2):336, 2021.
- Yun Jiang, Huixia Yao, Chao Wu, Wenhuan Liu. A Multi-Scale Residual Attention Network for Retinal Vessel Segmentation. Symmetry, 13(1):24, 2021.
- Chunfeng Zhang, Siguang An, Wei Wang, Dehui Lin. A Novel Meshing Method Based on Adaptive Size Function and Moving Mesh for Electromagnetic Finite Element Analysis. Symmetry, 13(2):254, 2021.
- Johannes Schönke, Michael Grunwald, Eliot Fried. Construction of Unknotted and Knotted Symmetric Developable Bands. Symmetry, 13(3):431, 2021.
- Francisco Fernández, Jorge Segovia. Historical Introduction to Chiral Quark Models. Symmetry, 13(2):252, 2021.
- Sharief Deshmukh, Hana Alsodais, Nasser Bin Turki. Some Results on Ricci Almost Solitons. Symmetry, 13(3):430, 2021.
- Deniz Can Kolukisa, Murat Ozbulut, Mehmet Yildiz. The Effect of Iterative Procedures on the Robustness and Fidelity of Augmented Lagrangian SPH. Symmetry, 13(3):472, 2021.
- Haitham Alsaif, Mohamed A. H. Eleiwa. Compact Design of 2 × 2 MIMO Antenna with Super-Wide Bandwidth for Millimeters Wavelength Systems. Symmetry, 13(2):233, 2021.
- Mahmoud A. Abd-Rabo, Mohammed Zakarya, Clemente Cesarano, Shaban Aly. Bifurcation Analysis of Time-Delay Model of Consumer with the Advertising Effect. Symmetry, 13(3):417, 2021.