$$L_{ve} = L_{vi} \Longrightarrow \sum \limits_i^{n_F} F_i^{(a)} \; \eta_i^{(b)} + \sum \limits_i^{n_R} R_i^{(a)} \; \gamma_i^{(b)} = \int \limits_\Lambda M^{(a)} \, \chi^{(b)} \; \mathrm{d} s + \int \limits_\Lambda T^{(a)} \, \gamma_{m}^{(b)} \; \mathrm{d} s + \int \limits_\Lambda N^{(a)} \, \varepsilon_{G}^{(b)} \; \mathrm{d} s $$