Selection Set - How do I select Block Reference Objects?

I have used selection sets before, like the example below to select all of
the light-weight polylines on the Bottom layer. Does anyone know how to
select just Block Reference objects? I tried to just replace LWPOLYLINE
with BLOCK REFERENCE, BLOCK, BLOCKREF, etc, but it didn't work.

'------------Start of Example------------
Dim CurSet As AcadSelectionSet
Dim SelCode(0 To 1) As Integer
Dim SelValue(0 To 1) As Variant

SelCode(0) = 8
SelValue(0) = "Bottom" 'look on Bottom layer
SelCode(1) = 0
SelValue(1) = "LWPOLYLINE" 'find lightweight polylines only

CurSet.Select acSelectionSetAll, , , SelCode, SelValue
'------------End of Example------------

Any help would be greatly appreciated.

 

A block reference is an "INSERT".......

 

I am currently using a For Next loop to evaluate the block reference names
in the selection set. So...if I know the name of the block reference is
there a way I can filter that too?

 

Sure, incresase the size of the arrays and add a 2 to the SelCode(2) and the
block name to SelValue(2)

 

Thanks again. I thought I'd post what I ended up with if anyone's
interested:

'------------Start of Example------------
Dim CurSet As AcadSelectionSet
Dim SelCode(0 To 2) As Integer
Dim SelValue(0 To 2) As Variant

Set CurSet = ThisDrawing.SelectionSets.Add("CutSelSet")

SelCode(0) = 8
SelCode(1) = 0
SelCode(2) = 2
SelValue(0) = "Drill" 'Look on Drill layer
SelValue(1) = "INSERT" 'only select block references
SelValue(2) = "SYMG*" 'only block names beginning with symg
CurSet.Select acSelectionSetAll, , , SelCode, SelValue
'------------End of Example------------