Has no exported member 'FirebaseListObservable'

Here is my error:

Module '"../../../../../../my-stuff/node_modules/angularfire2/database"' has no exported member 'FirebaseListObservable'.ts(2305)

import { Component } from '@angular/core';

import { AlertController } from '@ionic/angular';
import { Camera, CameraOptions } from '@ionic-native/camera';
import { GoogleCloudVisionServiceService } from '../google-cloud-vision-service.service';

import { AngularFireDatabase, FirebaseListObservable } from 'angularfire2/database';

@Component({
  selector: 'app-home',
  templateUrl: 'home.page.html',
  styleUrls: ['home.page.scss'],
})


export class HomePage {
  items: FirebaseListObservable<any[]>;
  constructor(
    private camera: Camera,
    private vision: GoogleCloudVisionServiceService,
    db: AngularFireDatabase,    
    private alert: AlertController) {
      this.items = db.list('items');
  }

  takePhoto() {
    const options: CameraOptions = {
      quality: 100,
      targetHeight: 500,
      targetWidth: 500,
      destinationType: this.camera.DestinationType.DATA_URL,
      encodingType: this.camera.EncodingType.PNG,
      mediaType: this.camera.MediaType.PICTURE
    }
    this.camera.getPicture(options).then((imageData) => {
      this.vision.getLabels(imageData).subscribe((result) => {
        this.saveResults(imageData, result.json().responses);
      });
    });
  }

  saveResults(imageData, results) {
    this.items.push({ imageData: imageData, results: results});     
  }
}