1. The non-regular, bipartite, integral graphs with maximum degree four, Part I: Basic properties;Balinska;Discrete Math.,2001
2. Harmonic graphs with small number of cycles;Borovićanin;Discrete Math.,2003
3. F.C. Bussemaker, D. Cvetković, There are exactly 13 connected cubic, integral graphs, Univ. Beograd, Publ. Elektrotehn. Fak., Ser. Mat. Fiz., Nos. 544–576, 1976, pp. 43–48.
4. D. Cvetković, Cubic integral graphs, Univ. Beograd, Publ. Elektrotehn. Fak., Ser. Mat. Fiz., Nos. 498–541, 1975, pp. 107–113.
5. Spectra of Graphs—Theory and Application;Cvetković,1995