OkhrimenkoS. A., & TamrazovP. M. (1999). Pairwise products of moduli of families of curves on a Riemannian Möbius strip. Ukrains’kyi Matematychnyi Zhurnal, 51(1), 110–116. Retrieved from https://umj.imath.kiev.ua/index.php/umj/article/view/4587