In the case of a vehicle the use of which is described in paragraph (3) or (4) of section
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(b) and which is not subject to a lease, the person who sold such vehicle to the person or entity using such vehicle shall be treated as the taxpayer that placed such vehicle in service, but only if such person clearly discloses to such person or entity in a document the amount of any credit allowable under subsection (a) with respect to such vehicle (determined without regard to subsection (c)).