To override the Content-type in your clients, use the HTTP Accept Header, append  the .xml suffix or  ?format=xml
        
        HTTP + XML
         The following are sample HTTP requests and responses. 
            The placeholders shown need to be replaced with actual values.
POST /Notary/AssignQueueDocument HTTP/1.1 
Host: api.securedsigning.com 
Accept: application/xml
Content-Type: application/xml
Content-Length: length
<AssignQueueDocumentRequest xmlns:i="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://schemas.datacontract.org/2004/07/SecuredSigning.Api.Rest.Requests">
  <DocumentReference>String</DocumentReference>
  <NotaryReference>String</NotaryReference>
  <PackageReference>String</PackageReference>
  <Send>false</Send>
</AssignQueueDocumentRequest>
 
HTTP/1.1 200 OK
Content-Type: application/xml
Content-Length: length
<SendToQueueResponse xmlns:i="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://schemas.datacontract.org/2004/07/SecuredSigning.Api.Rest.Models">
  <DocumentIDs xmlns:d2p1="http://schemas.microsoft.com/2003/10/Serialization/Arrays">
    <d2p1:string>String</d2p1:string>
  </DocumentIDs>
  <PackageName>String</PackageName>
  <PackageReference>String</PackageReference>
  <PackageStatus>String</PackageStatus>
</SendToQueueResponse>