Get data from other sheet

Get data from other sheet

Here I have two matters
- Get data from a sheet
In excel, i can do =Sheet1!A1. how to do it in Zoho Sheet?

- Get external data from another file
In excel, i can do =C:\.........\[Book2.xls]Sheet1!$A$1
How can I do it in Zoho Sheet?

Please, I appreciate your reply soon!