The following query should help you:
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:ser="http://www.ca.com/UnicenterServicePlus/ServiceDesk">
<soapenv:Header/>
<soapenv:Body>
<ser:doSelect>
<sid>894355008</sid>
<objectType>attached_sla</objectType>
<whereClause>_mapped_cr = 'cr:400251'</whereClause>
<maxRows>10</maxRows>
<attributes>
<!--1 or more repetitions:-->
<string>id</string>
<string>time_to_violation</string>
</attributes>
</ser:doSelect>
</soapenv:Body>
</soapenv:Envelope>