Sakharova Е. and Yampolsky, A. (2004) “Powers of the curvature operator of space forms and geodesics of the tangent bundle”, Ukrains’kyi Matematychnyi Zhurnal, 56(9), pp. 1231–1243. Available at: https://umj.imath.kiev.ua/index.php/umj/article/view/3837 (Accessed: 10 April 2025).