Donneby's
From Tardis Wiki, the free Doctor Who reference
Donneby's was a company based in Reigate which built rocket components.
In 1997, they built the nuclear reactors which powered the Mars 97. (PROSE: The Dying Days)
Behind the scenes
Donneby's was first mentioned in Doctor Who in an Exciting Adventure with the Daleks, in which Ian Chesterton fails to get a job as an assistant research scientist there.