Cannot use linq.js library on ionic 2 ts project

I need to use linq.js library in my app. I followed the following tutorial;
and, I import Enumerable like;
import {Enumerable} from 'linq'

However, when I tried to use it, visual studio code tells me [ts] Cannot find name 'Enumerable'.

I am struggling with this issue for 2 hours, please help me

Typings is no longer used.
You can do
npm install @types/linq --save

to get linqjs add type declarations for linq

or try