1/2 a^{a0}_{v0} b^{c0,c1}_{a1,a2} c^{a3,v2}_{c2,v1} eta1^{a1}_{a0} gamma1^{a2}_{a3} a+(c2) a+(v0) a+(v1) a-(v2) a-(c1) a-(c0)
-1/4 a^{a0}_{v0} b^{c0,c1}_{a1,a2} c^{a3,v2}_{c2,v1} lambda2^{a1,a2}_{a0,a3} a+(c2) a+(v0) a+(v1) a-(v2) a-(c1) a-(c0)