Anomalous Tunneling Systems in Amorphous Organic Materials
  We compare the heat release data of organic glasses with that of amorphous and glass like crystalline solids. Anomalous behavior was found in all these materials, which disagrees with the standard tunneling model. We can explain the most of the experimental observations within a phenomenological model, where we assume that for a part of tunneling systems the barrier heights are strongly reduced as a consequence of the local stress produced during the cooling process. 
S. Sahling, M. Kol\'a\v{c}, V.L. Katkov and V.A. Osipov
cond-mat.dis-nn