Filename in formula bar

Y

yee ven

How do you refer filename1 to a cell in the formula bar?
Example:

='\\Year 2004\September\[_filename1_.xls]sheet1'!$A$1

A | B
1 |
2 | filename1
3 |
4 |

="\\Year 2004\September\["_B2_".xls]sheet1'!$A$1
will not work
 
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