Function ch(client, ladate)
For n = 2 To Sheets("refs2").Range("A65536").End(xlUp).Row
If Sheets("refs2").Range("A" & n) = client And ladate >= Sheets("refs2").Range("B" & n) And ladate <= Sheets("refs2").Range("C" & n) Then
che = che & Sheets("refs2").Range("D" & n) & " & "
End If
Next n
ch = Left(che, Len(che) - 3)
End Function