Stupid LA tax return question

I just filed my return, and my online software gave me the option of direct debiting my account for the tax owed, or paying by check. No option for using a credit card. I didn't want to do debit my acct. Last year it gave me a little voucher to print out and send with the check, but it didn't do it this time. Anybody know the name/number of this form I'm supposed to send with the check, and where I might find a copy to print out?