  We find Baikov-Gazizov-Ibragimov approximate point symmetries of the
second-order Boussinesq ODE, and we find the higher-order approximate
symmetries corresponding to the unstable point symmetries (the point symmetries
that disappear fron the classification of the BGI approximate point symmetries)
of the unperturbed equation. Approximate local symmetries are used to construct
a general approximate solution of the Boussinesq ODE. We use approximate
integrating factors to find a general approximate solution of the
Benjamin-Bona-Mahony ODE reduction.
