1. E. Etourneau,Existence and connectivity of planar graphs having 12 vertices of degree 5 and n−12 vertices of degree 6, Infinite and finite sets (1975), North Holland.
2. S. Fanelli,On a conjecture on maximal planar sequences, J. Graph Theory,4, (1980), 371–375.
3. S. Fanelli,Due teoremi di non esistenza relativi ad una congettura di Schmeichel-Hakimi, Istituto Matematico dell'Università dell'Aquila, 1, (1980).
4. B. Grünbaum,Convex polytopes, (1967), Wiley Interscience.
5. S. L. Hakimi, E. F. Schmeichel,On the connectivity of maximal planar graphs, J. Graph Theory,2, (1978), 307–314.