Anisotropic power-law inflation for the Sáez–Ballester theory non-minimally coupled to a vector field Tuan Q. Do, Phung Van Dong, Duy H. Nguyen and J. K. Singh Eur. Phys. J. C, 85 6 (2025) 613 Published online: 04 June 2025 DOI: 10.1140/epjc/s10052-025-14331-6