digraph G {
    page="40,60"; 
    ratio=auto;
    rankdir=LR;
    fontsize=10;
   "agi" -> { rank=none; "pd" }
   "ak" -> { rank=none; "atb" }
   "e0" -> { rank=none; "afh" }
   "gu" -> { rank=none; "adg" }
   }