Laplace approximation reference

[taiya]

Rather than deriving this relationship via hard-coded rules, we follow the ideas in ~\todo{\cite{?}} and derive how this distribution can be approximated by a gaussian $\mathcal{N}(\star{x}_n, \star{\Sigma}_n)$.

Anastasia mentioned she has just used the wiki page. Could you help find a decent reference so we can get rid of the [?]