Unipolar graphs are interval filaments graphs. Brief sketch: If G is unipolar there are vertex sets A and B s.th A induces a clique and B induces a set of cliques with vertex sets B1, .., Bk, say. Create a filament for each vertex of G attached to the x-axis grouping them in order B1, ..., Bk, A. We can entangle the filaments in each group to create the cliques A, B1, ..., Bk in G. Any edge between A and Bk can then be created by having the filaments of their endpoints intersect close to the boundary between Bk and A. We place the intersections above all earlier intersections to avoid prohibited intersections. Once Bk is done, we continue with edges between B_(k-1) and A. And so on.
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