Sub Errare_Excelum_Est()
Dim vErr$, C As Range, NB_err&, x
For Each C In ActiveSheet.UsedRange.SpecialCells(xlCellTypeFormulas, 16)
vErr = vErr & "," & C.Parent.Name & "| " & C.Address(0, 0)
Next
x = Split(vErr, ",")
NB_err = UBound(x)
Sheets(2).[A1].Resize(NB_err) = Application.Transpose(x)
End Sub