Editing Penrose triangle (section)

==References==
{{reflist|refs=

<ref name=brorub>{{cite journal
 | last1 = Brouwer | first1 = James R.
 | last2 = Rubin | first2 = David C.
 | date = June 1979
 | doi = 10.1068/p080349
 | issue = 3
 | journal = [[Perception (journal)|Perception]]
 | pages = 349–350
 | title = A simple design for an impossible triangle
 | volume = 8| pmid = 534162
 | s2cid = 41895719
 }}</ref>

<ref name=ernst>{{cite conference
 | last = Ernst | first = Bruno
 | editor1-last = Coxeter | editor1-first = H. S. M. | editor1-link = Harold Scott MacDonald Coxeter
 | editor2-last = Emmer | editor2-first = M.
 | editor3-last = Penrose | editor3-first = R. | editor3-link = Roger Penrose
 | editor4-last = Teuber | editor4-first = M. L.
 | contribution = Escher's impossible figure prints in a new context
 | pages = 125–134
 | publisher = North-Holland
 | title = M. C. Escher Art and Science: Proceedings of the International Congress on M. C. Escher, Rome, Italy, 26–28 March, 1985
 | year = 1986}} See in particular p. 131.</ref>

<ref name=fedorov>{{Cite journal|last=Федоров|first=Ю.|date=1972|title=Невозможное-Возможно|journal=Техника Молодежи|volume=4|pages=20–21|url=http://zhurnalko.net/=nauka-i-tehnika/tehnika-molodezhi/1972-04--num22}}</ref>

<ref name=francis>{{cite book
 | last = Francis | first = George K.
 | contribution = Chapter 4: The impossible tribar
 | doi = 10.1007/978-0-387-68120-7_4
 | isbn = 0-387-96426-6
 | pages = 65–76
 | publisher = Springer
 | title = A Topological Picturebook
 | year = 1988}} See in particular p. 68, where Francis attributes this observation to [[John Stillwell]].</ref>

<ref name=gardner>{{cite journal
 | last = Gardner | first = Martin
 | date = August 1978
 | issue = 2
 | journal = [[Scientific American]]
 | jstor = 24960346
 | pages = 18–26
 | title = Mathematical Games: A Möbius band has a finite thickness, and so it is actually a twisted prism
 | volume = 239| doi = 10.1038/scientificamerican1278-18
 }}</ref>

<ref name=pappas>{{cite book
 | last = Pappas | first = Theoni | author-link = Theoni Pappas
 | contribution = The Impossible Tribar
 | location = San Carlos, California
 | page = 13
 | publisher = Wide World Publ./Tetra
 | title = The Joy of Mathematics: Discovering Mathematics All Around You
 | year = 1989}}</ref>

<ref name=penpen>{{cite journal
 | last1 = Penrose | first1 = L. S. | author1-link = Lionel Penrose
 | last2 = Penrose | first2 = R. | author2-link = Roger Penrose
 | date = February 1958
 | doi = 10.1111/j.2044-8295.1958.tb00634.x
 | issue = 1
 | journal = [[British Journal of Psychology]]
 | pages = 31–33
 | pmid = 13536303
 | title = Impossible objects: a special type of visual illusion
 | volume = 49}}</ref>

<ref name=wa>{{cite web|url=https://www.wa.gov.au/government/media-statements/Court%20Coalition%20Government/Unveiling-of-East-Perth-redevelopment%27s-latest-piece-of-public-art-19991105|title=Unveiling of East Perth redevelopment's latest piece of public art|date=5 November 1999|publisher=Government of West Australia|access-date=2025-05-09}}</ref>

}}