[1]
Theory of graphs and its applications. Proc. Symp. Smolenice 1963, Academia Prague 1964.
[2] J. Sedláček:
Local pгoperties of graphs. (Czech). Časopis pěst. mat. 106 (1981), 290-298.
MR 0629727
[3] L. Szamkolowicz:
On a classification of graphs with respect to the properties of neighbourhood gгaphs. In: Finite and Infinite Sets (Eger 1981), North-Holland 1984, 675-678.
MR 0818269