  The concept of directed strongly regular graphs was introduced by Duval in
his paper, A Directed Graph Version of Strongly Regular Graphs. Duval also
provided several construction methods for directed strongly regular graphs. The
directed strongly regular graphs reported in this paper are obtained using a
block construction of adjacency matrices of regular tournaments and circulant
matrices. We then give some algebraic and combinatorial interpretation of these
graphs in connection with known directed strongly regular graphs and related
combinatorial structures.
