The scintillation properties of luminescent crystals are well known at room temperature. It is only recently, for the sake of dark matter and rare events searches that the studies have been extended to very low temperatures in the millikelvin range. Some little-known facts on the behaviour of bolometers(1), and more specifically on scintillating ones, are recalled in a simple manner. A few experiments to better understand them are proposed. (C) 2008 Elsevier B.V. All rights reserved.