The Collected Works of Gustaf Heinrich Urnst

The Collected Works of Gustaf Heinrich Urnst was a book which reprinted the writings of Gustaf Urnst. It was published in June 2503. The Seventh Doctor owned a copy which he kept in his TARDIS. It was padlocked and leather-bound.

When the TARDIS detected a Fortean Flicker on the planet Hogsumm, it suggested that the Doctor and Bernice Summerfield consult the works of Urnst for additional information. In the book, they found in the last entry that Urnst had claimed to have discovered Sakkrat. (PROSE: The Highest Science)