  It is argued that the superposition approach, where partons are independently
emitted from longitudinally extended sources in the early stage, is fully
compatible with the experimental results for the forward-backward multiplicity
correlations in Pb+Pb collisions at $\sqrt{s_{NN}}=2.76 \textrm{ TeV}$. The
pertinent correlation analysis is based on the PhD Thesis of Ref. [1], which
includes an unpublished analysis of data taken by the ALICE Collaboration. Our
calculations show that in the experimentally covered pseudorapidity range
$\Delta \eta=1.2$, the initial sources in the backward and forward bins are
maximally correlated, which complies to the string-like interpretation of the
underlying early-stage production mechanism.
