Want source file name to be listed in results of Excel macro

I have just used the code provided in ID24183402.  It worked very well and I would like to be able to add the source file name to be listed in the results.  Thanks!

Sub FindAll()
   Dim wks As Worksheet, wksOut As Worksheet
   Dim colFoundRanges As Collection
   Dim strFind As String
   Dim lngIndex As Long
   On Error Resume Next
   Application.DisplayAlerts = False
   Sheets("Find results").Delete
   Application.DisplayAlerts = True
   Set wksOut = Worksheets.Add
   wksOut.Name = "Find results"
   
   Set colFoundRanges = New Collection
   
   strFind = InputBox("Enter string to find")
   For Each wks In ActiveWorkbook.Worksheets
      FindCells wks, strFind, colFoundRanges
   Next wks
   With colFoundRanges
      For lngIndex = 1 To .Count
         With .Item(lngIndex)
            wksOut.Cells(lngIndex, 1).Value = .Parent.Name
            wksOut.Cells(lngIndex, 2).Value = .Address
            wksOut.Cells(lngIndex, 3).Value = "'" & .Formula
         End With
      Next lngIndex
   End With
End Sub
Sub FindCells(ws As Worksheet, strToFind As String, colOutput As Collection)
   Dim strFirstAddress As String
   Dim rngFound As Range
   With ws.UsedRange
      Set rngFound = .Find(what:=strToFind, lookat:=xlPart, LookIn:=xlFormulas, MatchCase:=False)
      If Not rngFound Is Nothing Then
         strFirstAddress = rngFound.Address
         Do
            colOutput.Add rngFound, ws.Name & "-" & rngFound.Address
            Set rngFound = .FindNext(rngFound)
         Loop While rngFound.Address <> strFirstAddress
      End If
   End With
End Sub 

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