Links use name of external workbook entered once?

Hello!

I have 20 workbooks that all use one Sourcebook.xls for their data validation lists.

In the 20 workbooks themselves, they each have a Lists sheet that has hundreds of this type of formula:

=IF('M:\Server\JOBS\Blank Jobs Forms\[SourceBook.xls]Lists'!A2="","",'M:\Server\JOBS\Blank Jobs Forms\[SourceBook.xls]Lists'!A2)
=IF('M:\Server\JOBS\Blank Jobs Forms\[SourceBook.xls]Lists'!A3="","",'M:\Server\JOBS\Blank Jobs Forms\[SourceBook.xls]Lists'!A3)

Is there a way I can put the path in one cell and the rest of the formula in the other cells?

(Something like:

Z1: 'M:\Server\JOBS\Blank Jobs Forms\[SourceBook.xls]Lists'
A2: =IF(Z1&A2="","",z1&A2)
A3: =if(Z1&A3="","",Z1&A3)
)

Basically, I want to put the external workbook path into one place rather than every formula.

??

I appreciate any help!

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