  Conservation laws strongly influence production of particles in high-energy
particle collisions. Effects connected to these mechanisms were studied in
details using correlation techniques in \ee\ collisions. At the time, models
were tuned to correctly reproduce the measurements. Similar studies for
hadron-hadron collisions have never been performed, until recent ALICE
measurements. ALICE has reported on studies of untriggered two-particle angular
correlations of identified particles ($\pi$, $K$, and p) measured in pp
collisions at center-of-mass energy of $\sqrt{s}=$ 7 TeV. Those preliminary
results confirm that also in hadron-hadron collisions, at much higher energies,
conservation laws strongly influence the shape of the correlation functions for
different particle types and must be taken into account while analysing the
data. Moreover, they show that the contemporary models (PYTHIA, PHOJET) no
longer reproduce the experimental data well.
