two types for one element

[heras1985]

Hello, I have the next XML-Schema:

<xs:element name="classifying-space">
<xs:complexType>
<xs:choice>
<xs:group ref="SG"></xs:group>
<xs:group ref="ASG"></xs:group>
</xs:choice>
</xs:complexType>
</xs:element>

<xs:group name="ASG">
<xs:choice>
<xs:element ref="k-z"></xs:element>
<xs:element ref="k-z2"></xs:element>
</xs:choice>
</xs:group>

<xs:group name="SS">
<xs:choice>
<xs:element ref="sphere"></xs:element>
<xs:element ref="moore-space" ></xs:element>
<xs:element ref="sphere-wedge"></xs:element>
<xs:element ref="delta"></xs:element>
<xs:element ref="proj-space"></xs:element>
<xs:element ref="crts-prdc"></xs:element>
<xs:element ref="suspension"></xs:element>
</xs:choice>
</xs:group>

I want include the element classifying-space in the group SS if the choice in the element classifying space is SG, or include in the group ASG if the choice is ASG.
is it possible?
Thanks