Split slide into limited list ionic 2

ngFor i have 12 or more item, i need split show 3 heading in one slide, next 3 heading in next slide how to split and show

 private page = 0, pageSize = 3;
private list = []; // your array goes here

getItems() {
    let index = this.page * this.pageSize;
    return this.list.slice(index, index + this.pageSize);
}

<ion-slides pager  *ngFor="let item of getItems()">
   <ion-slide >
    <h2>{{item.text}}</h2>
   </ion-slide>
</ion-slides>