Other ways to enter cell references
Imagine that you want to know the combined cost for video rentals and CDs in February.
In cell C9, type the equal sign, type SUM, and type an opening parenthesis.
Click cell C4. The cell reference for cell C4 appears in cell C9. Type a comma after it in cell C9.
The example shows you how to enter a formula into cell C9 by clicking cells.