[1] M. Behzad G. Chartrand:
Introduction to the theory of gгaphs. Allyn and Bacon, Boston, 1971.
MR 0432461
[2] Z. Ryjáček: On graphs with isomorphic, non-isomorphic and connected N2-neighbouгhoods. Časopis pěst. mat. 112 (1987), 66-79.
[3] J. Sedláček:
Local properties of graphs. Časopis pěst. mat. 106 (1981), 290-298 (Czech, English summaгy).
MR 0629727
[4] J. Sedláček:
On local properties of finite graphs. In: Graph theory (Lagów 1981). Lecture Notes in Math. 1018, Springer-Verlag 1983, 242-247.
MR 0730654
[5] J. Sedláček:
Über eine spezielle Klasse von asymmetrischen Graphen. In: Graphen in Forschung und Unteгricht (Proc. Symp. Kiel, 1985), Baгbara Franzbecker-Verlag, 1985.
MR 0841557
[6] M. N. S. Swamy K. Thulasiraman:
Graphs, Networks and Algorithms. Ј. Wiley 1981.
MR 0605305