Equation 10.2.7A742A4B9C7C0

\begin{equation} Lf=\mathrm d^*\mathrm df=-\sum _{i,j}g^{ij}\partial _ i\partial _ jf+B_0\Bigl (\sum _ i\partial _ if\, \mathrm dx_ i\Bigr ); \end{equation}