Show that the following graph is planar or not.
My first assumption is that this graph is not planar, but could not find a reasonable prove (except saying that I tried drawing it in different ways in plane, but couldn't).
We know that a graph is non-planar if it contains either K5 or K3,3 as minors. I tried getting I subdivision of this graph (by contracting some edges), but failed to get a K5 (which I think should be possible).
Any ideas anyone?