If you have the voucher from an online purchase, you can scan it at one of the self service kiosks, to get your pass Nothing else is needed. The final part is when they scan your pass at the turnstiles they will take your picture. After that you are good to go.
I brought my smart phone and showed the receipt at the gate. They are are very familiar with that and do it all the time these days. Have a great time. Oh, btw, you should anyways have an actual ID with you just in case.
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