  The production of $t\overline{t}$, $W+b\overline{b}$ and $W+c\overline{c}$ is
studied in the forward region of proton-proton collisions collected at a
centre-of-mass energy of 8 TeV by the LHCb experiment, corresponding to an
integrated luminosity of 1.98 $\pm$ 0.02 $\mbox{fb}^{-1}$. The $W$ bosons are
reconstructed in the decays $W\rightarrow\ell\nu$, where $\ell$ denotes muon or
electron, while the $b$ and $c$ quarks are reconstructed as jets. All measured
cross-sections are in agreement with next-to-leading-order Standard Model
predictions.
