lases, so that we do get
| a well-defined product structure.
|
| Let X, Y be two manifolds.  Let f : X -&gt; Y be a map.
| We shall say that f is a &quot;C^p-morphism&quot; if, given x in X,
| there exists a chart (U, q) at x and a chart (V, r) at f(x)
| such that f(U) c V, and the map
|
| r o f o q^-1 : qU -&gt; rV
|
| is a C^p-morphism in the sense of Chapter 1, Section 3.
| One sees then immediately that this same condition holds
| for any choice of charts (U, q) at x and (V, r) at f(x)
| such that F(U) 