adding if else contribution for adding code repository as suggested in …

…https://datacite-metadata-schema.readthedocs.io/en/4.5/mappings/force11-software-citation/

xslt/software/xslt-software-transformation.xslt

@@ -2,6 +2,7 @@
 <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:datacite="http://datacite.org/schema/kernel-4" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:zbmath="https://zbmath.org/zbmath/elements/1.0/">
 <xsl:template match="/">
 <resource>
+
     <identifier>
         <xsl:value-of select="root/result/id"/>
     </identifier>
@@ -16,9 +17,20 @@
         <xsl:value-of select="root/result/description"/>
     </description>
 
-     <publisher>
-        <xsl:value-of select="root/result/homepage"/>
-    </publisher>
+    <xsl:choose>
+        <xsl:when test= "root/result/source_code != ''">
+            <!-- will be instantiated for item #1 and item #2 -->
+            <publisher>
+            <xsl:value-of select="root/result/source_code"/>
+            </publisher>
+        </xsl:when>
+        <xsl:otherwise>
+            <contributor contributorType="HostingInstitution">
+                <xsl:value-of select="root/result/homepage" />
+             </contributor>
+        </xsl:otherwise>
+    </xsl:choose>
+
 
 
     <xsl:for-each select="root/result/classification">
@@ -28,6 +40,7 @@
     <xsl:for-each select="root/result/related_software/id">
         <relatedIdentifier><xsl:value-of select="."/></relatedIdentifier>
       </xsl:for-each>
+
 </resource>
 </xsl:template>
 </xsl:stylesheet>