docs: function(params, callback) {
          /**
           * Callback for QB.users.delete(params, callback)
           * @callback deleteUserCallback
           * @param {object} error - The error object
           * @param {object} response - Empty body
           */
          var url;
  
          if (typeof params === 'number') {
              url = params;
          } else {
              if (params.external) {
                  url = 'external/' + params.external;
              }
          }
  
          this.service.ajax({url: Utils.getUrl(config.urls.users, url), type: 'DELETE', dataType: 'text'}, callback);
      }