a^{}_{} b^{a1}_{a0} c^{c1,a3}_{c0,a2} eta1^{a2}_{a1} gamma1^{a0}_{a3} a+(c0) a-(c1)
+a^{}_{} b^{a1}_{a0} c^{c1,a3}_{c0,a2} lambda2^{a0,a2}_{a1,a3} a+(c0) a-(c1)