Subbundle
In mathematics, a subbundle U of a vector bundle V on a topological space X is a collection of linear subspaces Ux of the fibers Vx of V at x in X, that make up a vector bundle in their own right.
In connection with foliation theory, a subbundle of the tangent bundle of a smooth manifold may be called a distribution.
If a set of vector fields Yk span the vector space U, and all Lie commutators are linear combinations of the Yk, then one says that U is an involutive distribution.
