1/2 a^{c1,a0}_{c0,a1} b^{a3,a4}_{a2,v0} c^{v2}_{v1} lambda2^{a1,a2}_{a3,a4} a+(c0) a+(v0) a+(v1) a-(v2) a-(a0) a-(c1)
-a^{c1,a2}_{c0,a1} b^{a0,a4}_{a3,v0} c^{v2}_{v1} eta1^{a3}_{a2} gamma1^{a1}_{a4} a+(c0) a+(v0) a+(v1) a-(v2) a-(a0) a-(c1)
-a^{c1,a2}_{c0,a1} b^{a0,a4}_{a3,v0} c^{v2}_{v1} lambda2^{a1,a3}_{a2,a4} a+(c0) a+(v0) a+(v1) a-(v2) a-(a0) a-(c1)