See notes related to the discussion of the torus within the hypercube
in Thomas F. Banchoff 's 1996 text Beyond the Third Dimension  .
The hypercube torus is more intelligible in the light of an
animation at the weblog post "Gleaming the Hypercube"—

http://www.log24.com/log/pix11C/11117-HypercubeFromMIQELdotcom.gif

(Animation source: MIQEL.com)