A simple analytical formula for mid-rapidity transverse-energy distributions is derived from the previously proposed multisource model for hadron-nucleus collisions. For p-Au and ${\ensuremath{\pi}}^{+}$-Au collisions at 200 GeV/nucleon, it turns out to be the same as the empirical formula obtained by the NA35 Collaboration. The multisource model is generalized to include nucleus-nucleus collisions. The observed target dependence of transverse-energy distributions in the most recent $^{16}\mathrm{O}$ on Al, Cu, Ag, and Au data is shown to be a natural consequence of the model.