How to use the onsenui/core-src/ons/ons.BackButtonElement function in onsenui

import TabbarElement from 'onsenui/core-src/elements/ons-tabbar';
import ToastElement from 'onsenui/core-src/elements/ons-toast';
import ToolbarButtonElement from 'onsenui/core-src/elements/ons-toolbar-button';
import ToolbarElement from 'onsenui/core-src/elements/ons-toolbar';

if (window.ons) {
  ons._util.warn('Onsen UI is loaded more than once.');
}

ons.TemplateElement = TemplateElement;
ons.IfElement = IfElement;
ons.ActionSheetElement = ActionSheetElement;
ons.ActionSheetButtonElement = ActionSheetButtonElement;
ons.AlertDialogElement = AlertDialogElement;
ons.AlertDialogButtonElement = AlertDialogButtonElement;
ons.BackButtonElement = BackButtonElement;
ons.BottomToolbarElement = BottomToolbarElement;
ons.ButtonElement = ButtonElement;
ons.CardElement = CardElement;
ons.CarouselItemElement = CarouselItemElement;
ons.CarouselElement = CarouselElement;
ons.ColElement = ColElement;
ons.DialogElement = DialogElement;
ons.FabElement = FabElement;
ons.GestureDetectorElement = GestureDetectorElement;
ons.IconElement = IconElement;
ons.LazyRepeatElement = LazyRepeatElement;
ons.ListHeaderElement = ListHeaderElement;
ons.ListTitleElement = ListTitleElement;
ons.ListItemElement = ListItemElement;
ons.ListElement = ListElement;
ons.InputElement = InputElement;