The forms that must be mailed can be found in your file that you can print and/or view. The same page should be part of your file. Please see the instructions below, but you can view your .pdf file without printing, then scroll through the pages to find the page noted in your question: "You've e-filed, but don't forget to mail in these forms". Remember that any forms or tax documents you mail to the IRS, you should also keep a copy of such as W2s or 1099s.
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