First photometric study of the contact binaries ZTF J181921.1 + 523627 and LINEAR_9406163Mohamed I. Nouh, Mohamed Abdel-Sabour, Ahmed Shokry, Essam Elkholy and A. S. SaadEur. Phys. J. Plus, 141 2 (2026) 203DOI: https://doi.org/10.1140/epjp/s13360-026-07411-3