104

Suplementary [condn?]

The proof was given in Part II. But the modification
needed is that s_ν is then considered as operator. However,
the following commutator
[s_μ(x), s_ν(x)]
[?] the proof. Since only the normal component of the space like
surface is needed, [s_μ, s₄(x)] = 0.

Gauge ħ and fn

The equation [is?] gauge invariant. (proof is the same as before)
Also the [?] equation can be taken over literally.