1. Bácś, S., Matsumoto, M.: On Finsler spaces of Douglas type A generalization of the notion of Berwald space. Publ. Math. Debrecen 51, 385–406 (1997)
2. Bácśo, S., Cheng, X.: Finsler conformal transformations and the curvature invariants. Publ. Math. Debrecen 70(1–2), 221–231 (2007)
3. Chern, S.S.: Finsler geometry is just Riemannian geometry without the quadratic restriction. Not. Am. Math. Soc. 43(9), 959–963 (1996)
4. Chen, G., Cheng, X., Zou, Y.: On conformal transformations between two $$(\alpha, \beta )$$-metrics. Differ. Geom. Appl. 31, 300–307 (2013)
5. Douglas, J.: The general geometry of paths. Ann. Math. 29, 143–168 (1927–1928)