# Foliation over characteristic positive

Ekedahl wrote about foliation in characteristic positive, over the field $/frac{Z}{pZ}$ as a subsheaft of the tangent sheaft, that is closed over involution and $p$-power, My question is if there exist aome reference about this theory but over the ring $/frac{Z}{p^{n}Z}$.

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Do you really mean the ring $\mathbb{Z}/p^{n}\mathbb{Z}$ or maybe the finite field $\mathbb{F}_{p^n}$ which is a field extension of $\mathbb{F}_p=\mathbb{Z}/p\mathbb{Z}$ ? If you do mean the first, what are some of your motivations? By the way, I think foliation theory can be defined over any field of positive characteristic as well. –  Qfwfq Nov 19 '12 at 14:33
Look at this paper: Miyaoka, Yoichi(J-TOKYM) Deformations of a morphism along a foliation and applications. Algebraic geometry, Bowdoin, 1985 (Brunswick, Maine, 1985), 245–268, Proc. Sympos. Pure Math., 46, Part 1, Amer. Math. Soc., Providence, RI, 1987. –  Sándor Kovács Nov 19 '12 at 16:50