.6 of
|         the inverse mapping theorem.
|
| The conditions expressed in [Propositions 2.2.1 and 2.2.2] depend only on the
| derivative [f'], and if they hold for one choice of charts (U, q) and (V, r),
| respectively, then they hold for every choice of such charts.  It is therefore
| convenient to introduce a terminology in order to deal with such properties.
|
| Let X be a manifold of class C^p (p &gt;= 1).
| Let x be a point of X.  We consider triples (U, q, v)
| where (U, q) is a chart at x and v is