/**
  * Find document owner signature object by document signature id and owner email
  *
  * @param int $documentSignatureId
  * @param string $email
  * @return DocumentOwnerSignature
  */
 public function findOneOwnerSignatureByDocumentSignatureIdAndOwnerEmail($documentSignatureId, $email)
 {
     return $this->ownerSignatureRepository->findOneByDocumentSignatureIdAndOwnerEmail($documentSignatureId, $email);
 }