Fiqh-us-Sunnah Volume 2, Supererogatory Prayer, Fiqh 2.045A.

The majority of the scholars are of the opinion that the sajdah is to be performed right after the recital or hearing of the ‘ayyah. Delaying such a sajdah does not rescind it. If an extended period of time lapses between recitation of an ‘ayah and the actual sajdah, one need not do it, for it does not have to be made up for.