Morteza Faghfouri - Department of Pure Mathematics, Faculty of Mathematical Sciences, University of Tabriz Tabriz. Iran E-mail: faghfouri@tabrizu.ac.ir

The class of semi-P-reducible Finsler metrics is a rich and basic class of Finsler metrics that contains the class of L-reducible metrics, C-reducible metrics, and Landsberg metrics. In this paper, we prove that every semi-P-reducible manifold with isotropic Landsberg curvature reduces to semi-C-reducible manifolds. Also, we prove that a semi-P-reducible Finsler metric of relatively isotropic mean Landsberg curvature has relatively isotropic Landsberg curvature if and only if it is a semi-C-reducible Finsler metric.

Finsler metric, semi-C-reducible metric, C-reducible metric