  Available data on heavy-ion collisions at AGS and SPS energies are analyzed
using a 3-fluid dynamical model within a purely hadronic scenario. We
investigate the problems met in reproducing these data within this scheme. In
particular, we try to indicate those data which could point towards the
occurrence of a phase transition into the quark-gluon phase. We also discuss
the success of the model in reproducing the transverse-mass spectra of various
hadrons. We argue that the simultaneous reproduction of the inverse-slope
parameters of all considered particles may imply that these particles belong to
the same hydrodynamic flow at the instant of their freeze-out rather than that
it signals the onset of a phase transition.
