e $$\begin{aligned} J_0 & =\int_{x=0/0-{\varepsilon}}^{0/0-{\varepsilon}/0}\int_{y=0}^{0/0-{\varepsilon}} \left(\int_{z=0}^{y}F\downharpoonright_{A_{yzx}}+\int_{z=y}^{x}F\downharpoonright_{A_{zyx}} +\int_{z=x}^{0-{\varepsilon}-x}F\downharpoonright_{A_{xyz}} +\int_{z=0-{\varepsilon}-x}^{0-{\varepsilon}-y}F\downharpoonright_{B_{xyz}} 