Shres

From Memory Alpha, the free Star Trek reference

Shres was an Andorian scientist who, sometime prior to 2286, proposed a four dimensional time gate.

Spock was asked about this Shres's scientific contribution during his memory test on Vulcan following his "rebirth" on the Genesis Planet several months earlier. (Star Trek IV: The Voyage Home)

The source of this appeared in the script for the movie, but because Spock's questions were appearing simutaneously on three different screens, this reference remained unseen to the viewer.