code: function getOrder(account, identifier, callback) {
    validate.address(account);
    validate.identifier(identifier);
  
    var txRequest = this.remote.requestTx({
      hash: identifier
    });
  
    txRequest.once('error', callback);
    txRequest.once('transaction', function(response) {
      if (response.TransactionType !== 'OfferCreate'
          && response.TransactionType !== 'OfferCancel') {
        callback(new InvalidRequestError('Invalid parameter: identifier. '
          + 'The transaction corresponding to the given identifier '
          + 'is not an order'));
      } else {
        var options = {
          account: account,
          identifier: identifier
        };
        asyncify(TxToRestConverter.parseOrderFromTx)(response, options, callback);
      }
    });
    txRequest.request();
  }
docs: Get an Order transaction (`OfferCreate` or `OfferCancel`)
  
  @url
  @param {RippleAddress} request.params.account
  @param {String} request.params.identifier
  
  @param {Express.js Request} request