Question: How do you sum over multiple indexes when your Hamiltonian contains operators with more than one index?

I am trying to derive Heisenberg's equation of motion for an observable given by two Fermionic operators. The Hamiltonian has both Fermionic and Bosonic creation and annihilation operators.  

H := sum(g[`q&alpha;&beta;`]*C[alpha]*v[beta]*b[q]-g[`q&alpha;&beta;`]*B[q]*V[beta]*c[alpha], `q&alpha;&beta;`)

When I take the commutator with 

A := C[nu]*c[nu]

and try to simplify down it will only go so far. I know the final answer and have checked what it gives by hand, but it will not sum over the different indexes. 

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