In http://www.accesstoinsight.org/tipitaka/dn/dn.16.1-6.vaji.html
I find the following:
The blessed one’s prompting Chapter 3 verse 3-6
in the Maha-parinibbana Sutta
3. And the Blessed One said: "Whosoever, Ananda, has developed, practiced, employed, strengthened, maintained, scrutinized, and brought to perfection the four constituents of psychic power could, if he so desired, remain throughout a world-period or until the end of it. [The Tathagata, Ananda, has done so. Therefore the Tathagata could, if he so desired, remain throughout a world-period or until the end of it."
4. But the Venerable Ananda was unable to grasp the plain suggestion, the significant prompting, given by the Blessed One. As though his mind was influenced by Mara, he did not beseech the Blessed One: "May the Blessed One remain, O Lord!. May the Happy One remain, O Lord, throughout the world-period, for the welfare and happiness of the multitude, out of compassion for the world, for the benefit, well being, and happiness of gods and men!"
5. And when for a second and a third time the Blessed One repeated his words, the Venerable Ananda remained silent.
6. Then the Blessed One said to the Venerable Ananda: “Go now, Ananda, and do as seems fit to you.”
How would I reference these verses in Sutta Central?