EN
We give new and general sufficient conditions for a Gaussian upper bound on the convolutions $K_{m+n} ∗ K_{m+n-1} ∗ ⋯ ∗ K_{m+1}$ of a suitable sequence K₁, K₂, K₃, ... of complex-valued functions on a unimodular, compactly generated locally compact group. As applications, we obtain Gaussian bounds for convolutions of suitable probability densities, and for convolutions of small perturbations of densities.