I don't see any 4D inside that :)
You can built this very easily
So that is a Klein's Cube? Yes you right :)


From JP Petit "Le topologicon" all about Topology in very undestanding in Comics book format PDF !

Exist in English (it's free ;)
Choose your language
here the Topologicon http://www.savoir-sans-frontieres.com/JPP/telechargeables/English/topo_the_world_eng.htm

Here all the books on some scientic subjects : All is free: a true gem !
And you translate some books if you want!
http://www.savoir-sans-frontieres.com/