Origins of the Universe

Origins of the Universe was a book by Oolon Colluphid, which the Fourth Doctor was reading around the time of Romana's first regeneration and an encounter with the Daleks. He found Colluphid's conclusions to be laughable and suggested the author "ask someone who saw it happen", in particular about the very first lines and the nature of the planet Magla. (TV: Destiny of the Daleks)

Behind the scenes
Oolon Colluphid is a character in Douglas Adams's The Hitchhiker's Guide to the Galaxy. At the time Destiny of the Daleks was produced, Adams was script editor on Doctor Who and was also preparing the radio series (and later book series) of Hitchhiker's Guide. The reference to Colluphid has raised the question as to whether the Whoniverse and the Hitchhiker's Guide universe either intersect or have commonality. A later reference to Arthur Dent (TV: The Christmas Invasion) was similarly vague, though Arthur and Zaphod Beeblebrox appear in the 2003 animation of Shada, so it is more likely the Tenth Doctor personally knew Arthur as opposed to enjoying a story with Arthur in.