I found a topic see below, but can't find an IRS publication about it please help.
One extremely favorable U.S. Internal Revenue Service announcement has ruled that if a nonresident alien sells an asset prior to becoming a Resident Alien for a promissory note and not immediate cash, the proceeds of the note when received will not be considered taxable even after the residency starting date. The sale is considered to be completed and the funds are earned for tax purposes when the sale took place during the Taxpayer’s Non Resident Alien statue.
One extremely favorable U.S. Internal Revenue Service announcement has ruled that if a nonresident alien sells an asset prior to becoming a Resident Alien for a promissory note and not immediate cash, the proceeds of the note when received will not be considered taxable even after the residency starting date. The sale is considered to be completed and the funds are earned for tax purposes when the sale took place during the Taxpayer’s Non Resident Alien statue.