<?xml version="1.0" encoding="UTF-8"?>
<xs:schema attributeFormDefault="unqualified" elementFormDefault="qualified" targetNamespace="b" xmlns:xs="http://www.w3.org/2001/XMLSchema">
  <xs:element name="b">
    <xs:complexType mixed="true">
      <xs:sequence>
        <xs:element ref="c:c" xmlns:c="c"/>
      </xs:sequence>
      <xs:attribute type="xs:string" name="c" use="optional" xmlns:xs="http://www.w3.org/2001/XMLSchema"/>
    </xs:complexType>
  </xs:element>
</xs:schema>