on which does give an isomorphism onto a submanifold is
| called an &quot;embedding&quot;, and it is called a &quot;closed embedding&quot; if
| this submanifold is closed.
|
| A morphism f : X -&gt; Y will be called a &quot;submersion&quot; at a point x in X
| if there exists a chart (U, q) at x and a chart (V, r) at f(x) such that
| q gives an isomorphism of U on a product U_1 x U_2 (U_1 and U_2 open in
| some Banach spaces), and such that the map
|
| rfq^-1  =  f_V,U : U_1 x U_2 -&gt; V
|
| is a projectio