passing a variable to Page Header

[carsto]

my variable RefNum doesn't pass to the Page Header

RefNum = InputBox("What is the Reference Number?")

    Sheets("Image").Select
        With ActiveSheet.PageSetup
            .LeftHeader = "&""Arial,Bold""&14RefNum"
        End With

If I don't include the formatting info it works but I'd like it fomatted

.LeftHeader = RefNum