author =       "R. Bar-Yehuda and T. Etzion",
  title =        "Connections between Two Cycles -- {A} New Design of
                 Dense Processor Interconnection Networks",
  journal =      "Discrete Applied Mathematics and Combinatorial
                 Operations Research and Computer Science",
  volume =       "38",
  pages =        "29--43",
  year =         "1992",
  abstract =     "In this paper we attempt to maximize the order of
    graphs of given degree $\Delta$ and diameter $D$.
    These graphs, which are known as $(\Delta,D)$ graphs,
    are used as dense interconnection networks, i.e.,
    processors with relatively few links are connected
    with relatively short paths. The method described in
    this paper uses periodic connections between two
    cycles of the same length. The results obtained give
    a significant improvement of the known lower bounds
    in many cases.  Large bipartite graphs with a given
    degree and diameter were also obtained by our method.
    Again, the improvement of the lower bounds is significant.",