Which expression is correct when we use the prepositions with or by for indicating that the reduction is carried out using $\ce{NaBH4}$ as a reductor:
It is reduced to sodium phenylselenolate with $\ce{NaBH4}$ in alkaline ethanol.
or:
It is reduced to sodium phenylselenolate by $\ce{NaBH4}$ in alkaline ethanol.