|It's basically done the same way as any other =A1 or =Sheet2!A1 is done, except that the formula will include the file name.|
The easiest way is to follow these steps:
Open both files.
Enter an equal sign in File2.xls Sheet1 A1 and then click in File1.xls Sheet1 A1.
With File1.xls open, you'll see the File name, Sheet name and cell reference.
When you close File1.xls, the formula will automatically change to include the full path to the file.
='C:\Documents and Settings\user name\My Documents\[File1.xls]Sheet1'!$A$1
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