(EN) The proposed bilateral project stands at the cutting edge of today's research in Algebraic Graph Theory and in Theory of incident structures, as well as applications of these theories in other sciences. The importance of our research goals can be seen in project team members’ bibliographies, their citations, and numerous links with scientists around the world. The outcome of this project will have a great impact on the development of both, the Algebraic Graph Theory and the Theory of Incident structures, as well as in related fields, and will give a strong impetus to the Slovenian and Croatian Algebraic Graph Theory School and Incident Structures school. The project would help project team members to keep in touch with trends in modern mathematics, especially in Algebraic graph theory and in Theory of incidence structures.