Non-orientable surfaces in 4-dimensional space
Yongju Bae, J. Scott Carter, Seonmi Choi, Sera Kim · Journal of Knot Theory and Its Ramifications · 2014
This paper is a survey paper that gives detailed constructions and illustrations of some of the standard examples of non-orientable surfaces that are embedded and immersed in 4-dimensional space. The illustrations depend upon their 3-dimensional projections, and indeed the illustrations here depend upon a further projection into the plane of the page. The concepts used to develop the illustrations will be developed herein.