One combobox link to TWO comboxes

Hello everybody,

It is my first request on this forum, I already found several answers for my ACCESS 2010 issues but now I have another one.
I would like to link one combobox to TWO comboboxes:
- Combobox to link: cboArea
- to TWO comboxes:
cboSubzone
cbo Floor

cboSubzone is already linked to another combobox cboZone
So here's the order of the cascading comboboxes
Zone - SubZone - Floor Level - Area

I have the beginning of a code but don't know how to finish it...any thoughts please? :confused:

Private Sub cboZone_AfterUpdate()
On Error Resume Next
Select Case cboZone.Value
Case "Zone A"
cboSubzone.RowSource = "2-1ZoneASubZones"
Case "Zone B"
cboSubzone.RowSource = "2-2ZoneBSubZones"
Case "Zone C"
cboSubzone.RowSource = "2-3ZoneCSubZones"
Case "Zone D"
cboSubzone.RowSource = "2-4ZoneDSubZones"
Case "Zone E"
cboSubzone.RowSource = "2-5ZoneESubZones"
Case "Zone F"
cboSubzone.RowSource = "2-6ZoneFSubZones"
Case "Zone G"
cboSubzone.RowSource = "2-7ZoneGSubZones"
Case "Zone H"
cboSubzone.RowSource = "2-8ZoneHSubZones"
Case "Zone I"
cboSubzone.RowSource = "2-9ZoneISubZones"
Case "Zone J"
cboSubzone.RowSource = "2-10ZoneJSubZones"
End Select
End Sub

Private Sub cboSubzone_AfterUpdate()
On Error Resume Next
Select Case cboSubzone
Case "Connectivity"
cboArea.RowSource = "4-Zone A SubZone 01 Areas"
Case "Co-Mtg"
cboArea.RowSource = "4-Zone A SubZone 01 Areas"
.........................................................
End Select
End Sub