Question : How to fill a series -I think? Excel 2007

If I have a formula
=IF([Documentation.xlsx]Sheet1!$A$1="","",[Documentation.xlsx]Sheet1!$A$1)
and my next cell down should read
=IF([Documentation.xlsx]Sheet1!$A$2="","",[Documentation.xlsx]Sheet1!$A$2)
and my next cell down should read
=IF([Documentation.xlsx]Sheet1!$A$3="","",[Documentation.xlsx]Sheet1!$A$3)

Is there a way to copy the formula down so I do not have to hand edit each formula?

Answer : How to fill a series -I think? Excel 2007

Yes, remove the $ before the 1.

=IF([Documentation.xlsx]Sheet1!$A1="","",[Documentation.xlsx]Sheet1!$A1)