Owing to symmetry, this expression can also be written in the form

= -1/4 [_g_^{μα} _g_^{νβ} F_{αβ} ∂F_{μν}/∂_x__{σ}

+ _g_^{μα} _g_^{νβ} ∂F_{αβ}/∂_x__{σ} F_{μν}],

which can also be put in the form

- 1/4 ∂/∂_x__{σ} (_g_^{μα} _g_^{νβ} F_{αβ} F_{μν})

+ 1/4 F_{αβ} F_{μν} ∂/∂_x__{σ} (_g_^{μα} _g_^{νβ}).