Angular/WpRestApi как получить значение Headers из ответа?

this.get()
      .subscribe(
        e => {
          console.log(e.headers.get('X-WP-Total'));
        });

core.js:1427 ERROR TypeError: Cannot read property 'get' of undefined

this.get()
      .subscribe(
        e => {
          console.log(e.headers);
        });