1. Extending maps of plane Peano continua;Adkisson;Duke Math. J.,1940
2. Graph Theory;Bollobás,1979
3. First Concepts of Topology;Chinn,1966
4. On the straight line representation of planar graphs;Fáry;Acta Sci. Math. (Szeged),1948
5. On the dimension of partially ordered sets;Kelly;Discrete Math.,1981