axiom:*
*->Ab<A>a
A->BDEbdaG
B->[bdga,9]
C->[bdabde,9]
D->[Cbda,8]
E->[bdabf,9]
F->[abcbfb,9]
G->[bFabcbaI<F>,4]
H->[bcbebcba,9]
I->[Hbcba,8]