L =\int_{\rho_0}^{\rho} \frac{ \rho1/c(\rho) - j_m^2/\rho }{G \, \rho^2 - F(\rho)} \, d\rho
=\int_{p_0}^{p} \frac{ \rho(p) - j_m^2 \, c(p) }{G \, \rho^2(p) - F(\rho(p))} \, dp =
\int_{p_0}^{p} \frac{ \rho \, dp}{G \, \rho^2 - F(\rho)}
- j_m^2 \cdot \int_{\rho_0}^{\rho} \frac{1}{\rho} \, \frac{d \rho}{G \, \rho^2 - F(\rho)}
|