ADDRESS

Returns a text reference to a single cell in a worksheet.
A1: =ADDRESS(2,3) => $C$2
A2: =ADDRESS(2,3,2) => C$2
A3: =ADDRESS(2,3,2,FALSE) => R2C[3]
A4: =ADDRESS(2,3,1,FALSE,"[Book1.xlsx]Sheet1") => '[Book1.xlsx]Sheet1'!R2C3
A5: =ADDRESS(2,3,1,FALSE,"EXCEL SHEET") => 'EXCEL SHEET'!R2C3