5.15 http://schemas.microsoft.com/office/spreadsheetml/2014/revision Schema

 <xsd:schema targetNamespace="http://schemas.microsoft.com/office/spreadsheetml/2014/revision" elementFormDefault="qualified" xmlns="http://schemas.microsoft.com/office/spreadsheetml/2014/revision" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:x="http://schemas.openxmlformats.org/spreadsheetml/2006/main" xmlns:xr6="http://schemas.microsoft.com/office/spreadsheetml/2016/revision6" xmlns:xr10="http://schemas.microsoft.com/office/spreadsheetml/2016/revision10">
   <xsd:import namespace="http://schemas.openxmlformats.org/spreadsheetml/2006/main" schemaLocation="xlbasictypes.xsd"/>
   <xsd:import namespace="http://schemas.openxmlformats.org/spreadsheetml/2006/main" schemaLocation="xlstyles.xsd"/>
   <xsd:import namespace="http://schemas.microsoft.com/office/spreadsheetml/2016/revision6" schemaLocation="xlrevexignore6.xsd"/>
   <xsd:import namespace="http://schemas.microsoft.com/office/spreadsheetml/2016/revision10" schemaLocation="xlrevexignore10.xsd"/>
   <xsd:simpleType name="ST_Xrevid">
     <xsd:restriction base="xsd:unsignedLong"/>
   </xsd:simpleType>
   <xsd:complexType name="CT_RevisionPtr">
     <xsd:attribute name="revIDLastSave" type="ST_Xrevid" use="required"/>
     <xsd:attribute name="documentId" type="x:ST_Xstring" use="required"/>
     <xsd:attribute ref="xr6:coauthVersionLast" use="optional" default="0"/>
     <xsd:attribute ref="xr6:coauthVersionMax" use="optional" default="0"/>
     <xsd:attribute ref="xr10:uidLastSave" use="optional"/>
   </xsd:complexType>
   <xsd:attribute name="uid" type="x:ST_Guid"/>
   <xsd:element name="revisionPtr" type="CT_RevisionPtr"/>
 </xsd:schema>