[ubl-ndrsc] Namespace Transitivity

[Matthew Gertner <matthew.gertner@acepoint.cz>]

From the XML Schema spec (Structures):

"Schema Representation Constraint: QName resolution (Schema Document) 

For a *QName* to resolve to a schema component of a specified kind all
of the following must be true:
1 That component is a member of the value of the appropriate property of
the schema which corresponds to the schema document within which the
*QName* appears, that is the appropriate case among the following must
be true:
1.1 If the kind specified is simple or complex type definition, then the
property is the {type definitions}.
1.2 If the kind specified is attribute declaration, then the property is
the {attribute declarations}.
1.3 If the kind specified is element declaration, then the property is
the {element declarations}.
1.4 If the kind specified is attribute group, then the property is the
{attribute group definitions}.
1.5 If the kind specified is model group, then the property is the
{model group definitions}.
1.6 If the kind specified is notation declaration, then the property is
the {notation declarations}.
2 its {local name} matches the *local name* of the *QName*; 
3 its {target namespace} is identical to the *namespace name* of the
*QName*; 
4 its *namespace name* is either the target namespace of the schema
document containing the *QName* or that schema document contains an
<import> element information item the *actual value* of whose namespace
[attribute] is identical to that *namespace name*."

As described in point 4, for a namespace to be referenced it MUST be
imported explicitly (or be the target namespace of the schema in
question). If a namespace is imported by an imported schema it is not
accessible (i.e. namespace imports are not transitive).

Matt