toplevel "A";
"A" and "B" "C";
"B" wsp "I" "J" "K";
"C" wsp "M" "J";
"I" lambda=0.5 dorm=0.3;
"J" lambda=0.5 dorm=0.3;
"K" lambda=0.5 dorm=0.3;
"M" lambda=0.5 dorm=0.3;