On Sesame Tree, Potto utilizes his library's books as a means of gathering new information about the world around him. The characters who supply Potto with his books are the Bookworms, Samson and Goliath, who reside with Potto, Hilda and Archie in the Sesame Tree. The books are used in many episodes and are a source of great assistance to Hilda as she journeys out into Northern Ireland.
EPISODE: "The Bookworms Move House" -- BOOK: "Learn to Talk Binary" (book not used by Hilda or Potto)
EPISODE: "The Share Necessities" -- BOOK: "The Share Necessities"
EPISODE: "Different Ways of Telling Stories" -- BOOK: "How I Learned to Stop Worrying and Tell a Story"
(http://www.bbc.co.uk/northernireland/schools/sesame/grown_ups/s1_tv_programmes/ BBC - Sesame Tree - Grownups)