Lacunary Finsler spaces

In this paper we consider motions in Finsler spaces. We prove the following theorem.
Theorem. {\it The maximal order of groups of motions $G_r$ in Finsler spaces $F_{n,\dot x}$ with nonzero tensor $F_{\cdot \,i\,\cdot\,j\,\cdot\,k}$ is exactly equal to $\frac{n(n-1)}2+2$.}
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