somme d'une cellule dans tout un classeur

Sub Macro1()
Dim Somme As Long
Dim Ctr As Integer
Somme = 0
For Ctr = 1 To Sheets.Count
'If (Sheets(Ctr).Name > 1000) And (Sheets(Ctr).Name < 9999) Then
'pas besoin de select
'Sheets(Ctr).Select
Somme = Somme + Sheets(Ctr).Range("D1").Value
'End If
Next
' idem plus haut
'Sheets("Result").Select
Sheets("Result").Range("A1").Value = Somme
End Sub

Dim Ctr as variant
Dim Ligne as integer
Dim Colonne as integer

Colonne = [B][COLOR="Orange"]1[/COLOR][/B]
Ligne = [COLOR="Blue"][B]1[/B][/COLOR]


  For Ligne = [COLOR="Blue"][B]1[/B][/COLOR] To [COLOR="Red"][B]15[/B][/COLOR]
      Ctr = Sheets("Result").Cells(Ligne, Colonne)
  Next Ligne

Sub Macro1()
Dim Somme As Long
Dim Ws As Worksheet

  For Each Ws In ThisWorkbook.Sheets
    If Ws.Name <> "Result" Then
      Somme = Somme + Ws.Range("D1").Value
    End If
  Next Ws
  Sheets("Result").Range("A1").Value = Somme
End Sub