Hyperbolic and trigonometric hypergeometric solutions to the star-star equation Erdal Catak, Ilmar Gahramanov and Mustafa Mullahasanoglu Eur. Phys. J. C, 82 9 (2022) 789 Published online: 05 September 2022 DOI: 10.1140/epjc/s10052-022-10661-x