2 . p q l GLYPH<c109> p-l p+q-l p+q GLYPH<c97> GLYPH<c98> GLYPH<c108> GLYPH<c114> = − ie Λ µ $_{b}$( p, p + q ) e ip ∧ q (81) = ∫ d $^{4}$l (2 π ) 4 − ig$_{αβ}$ ( p + q − l ) 2 − ig$_{λρ}$ ( p − l ) $_{2}$( − ieγ $^{α}$) iS$_{0}$ ( l )( − ieγ $^{λ}$) × (2 e ) γ $^{µβρ}$( q, − p − q + l, p − l ) 1 2 i ( 1 − e 2 il ∧ $^{q}$e − 2 ip ∧ q ) e ip ∧ $^{q}$, PP[ − ie Λ µ $_{b}$( p, p + q )] = 3 16 π 2 1 ϵ γ µ (82) Z$_{1}$$_{F}$ = 1 − 3 16 π 2 1 ϵ , (83) q$_{µ}$ Λ µ $_{b}$( p, p + q ) = ∫ d $^{4}$l (2 π ) 4 − ig$_{αβ}$ ( p + q − l ) 2 − ig$_{λρ}$ ( p − l ) $_{2}$( − ieγ $^{α}$) iS$_{0}$ ( l )( − ieγ $^{λ}$) ( 1 − e 2 il ∧ $^{q}$e − 2 ip ∧ q ) × { ( p + q − l ) $^{ρ}$qβ + ( p − l ) $^{β}$qρ − [( p + q − l ) · q + ( p − l ) · q ] g βρ } , (84) ( p + q − l ) $^{ρ}$qβ + ( p − l ) $^{β}$qρ = ( p + q − l ) $^{ρ}$( p + q − l ) β − ( p − l ) $^{ρ}$( p − l ) $^{β}$, and ( p + q − l ) · q + ( p − l ) · q = ( p + q − l ) 2 − ( p − l ) $^{2}$, (85) q$_{µ}$ Λ µ $_{b}$( p, p + q ) = Σ( p ) − Σ( p + q ) − Σ$_{np}$( p ) + Σ$_{np}$( p + q ) (86) + ∫ d $^{4}$l (2 π ) 4 i ( p + q − l ) 2 i ( p − l ) $_{2}$( ie )( / p + / q − / l ) iS$_{0}$ ( l )( ie )( / p + / q − / l ) ( 1 − e 2 il ∧ $^{q}$e − 2 ip ∧ q ) − d $^{4}$l (2 π ) 4 i ( p + q − l ) 2 i ( p − l ) $_{2}$( ie )( / p − / l ) iS$_{0}$ ( l )( ie )( / p − / l ) ( 1 − e 2 il ∧ $^{q}$e − 2 ip ∧ q ) , q q q-l l GLYPH<c97> GLYPH<c98> = iq $^{2}$b ( q $^{2}$) (87) 13 whose planar part logarithimically diverges. In fact its pole part (PP) is given by so that, in the minimal dimensional regularization scheme, which agrees with the result of previous calculation [12]. Contracting q$_{µ}$ in the expression (81), we get which may be further simplified using to yield where Σ is similar to Σ$_{np}$ of Eq. (80), but without the phase factor. For the last term in left-hand side of Eq. (76), we get