digraph mux {
    rankdir = LR;

    if0 [shape=triangle, orientation=270];
    if1 [shape=triangle, orientation=270];
    prenot [shape=point, width=0];
    not [shape=triangle, orientation=180];

    in0 [shape=point];
    sel [shape=point];
    in1 [shape=point];

    preout [shape=point, width=0];
    out [shape=point, label=out];

    edge [weight=1];

    sel -> prenot [label=select, arrowhead=none];
    prenot -> if1 [arrowhead=normal, tailport=s, headport=n];
    prenot -> not [headport=n];
    in0 -> if0 [label=in0, headport=w];
    in1 -> if1 [label=in1, headport=w];

    if0 -> preout [tailport=e, arrowhead=none];
    if1 -> preout [tailport=e, arrowhead=none];

    preout -> out [label=out];

    not -> if0 [weight=42, headport=n, tailport=s, arrowtail=invodot];

    {rank=same; sel ; in0 ; in1; }
    {rank=same; if0 ; if1; prenot; not;}
}