Re: IDREFS types in schemas

xs:ID (I think that's what you want for inp), xs:IDREF and xs:IDREFS
function the same as they do in DTDs -- see any introductory XML book
for details.

Something like

<xs:element name="GInP">
 <xs:complexType>
  <xs:sequence>
   . . .
  </xs:sequence>
  <xs:attribute name="inp" type="xs:ID" use="required"/>
 </xs:complexType>
</xs:element>

<xs:element name="Correspondance">
 <xs:complexType>
  <xs:sequence>
   . . .
  </xs:sequence>
  <xs:attribute name="corresplist" type="xs:IDREFS"/>
 </xs:complexType>
</xs:element>

or maybe I have the attributes on the wrong elements, I wasn't sure
from your description.

See the Primer [1] for an overall introduction to elements and types,
and also the more powerful schema-native key and keyref.

ht

[1] http://www.w3.org/TR/xmlschema-0/
-- 
  Henry S. Thompson, HCRC Language Technology Group, University of Edinburgh
                      Half-time member of W3C Team
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	    Fax: (44) 131 650-4587, e-mail: ht@cogsci.ed.ac.uk
		     URL: http://www.ltg.ed.ac.uk/~ht/
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