found: LCSH(Tunnel books. UF Peep show books; Peepshow books. BT Toy and movable books)
found: Reitz, J.M. ODLIS : online dictionary for library and information science, July 28, 2014(tunnel book: A novelty book in which the pages are bound at both sides and separable accordion-style, allowing the user to look through an opening in the front page to view, as if in three dimensions, a scene depicted on subsequent pages. Synonymous with peepshow book. See also: carousel book; carousel book: A type of tunnel book that opens in a circle to reveal, in three dimensions, several scenes in the story)
found: Wikipedia, 22 July 2010:Pop-up book (under Pop-up types: Tunnel books (also called peepshow books) consist of a set of pages bound with two folded concertina strips on each side and viewed through a hole in the cover; the term "tunnel book" derives from the fact that many of these books were made to commemorate the building of the tunnel under the Thames River in London in the mid-19th century)
found: Smithsonian Libraries website search, 22 July 2011:Dance of the tunnel book (Tunnel books or peep shows are a series of cut-paper panels placed one behind the other, creating the illusion of depth and perspective)
found: Tunnel Vision Books website, 22 July 2011:About us (tunnel books; inspired by Victorian paper toys, have intricately-cut layers attached to accordion sides)
found: Hutchins, E.H. Exploring tunnel books, via WWW (Google cached site), July 22, 2011(tunnel books; Peter Haining includes these "toy books" in Movable Books; peep shows; peepshows; peep show book; the tunnel or peep show book format)
