Function GRG2ISO(dGRG)
Dim a, b, g
g = Array("", "", "")
If IsDate(dGRG) Then
If Int(dGRG) > 0 And Int(dGRG) <> 60 Then
b = Int(dGRG) - (dGRG < 60) + 5
a = DateSerial(Year(b - b Mod 7 - 2), 1, 1)
g = Array(Year(a), (b - b Mod 7 - a + 5) \ 7, b Mod 7 + 1)
End If
End If
GRG2ISO = g
End Function