Influence of the electric field on the latent heat of the ferroelectric   phase transition in KDP
  The specific heat, heat flux (DTA trace) and dielectric constant of KDP ferroelectric crystal have been measured simultaneously for various electric fields with a conduction calorimeter. The specific heat presents a strong anomaly but these simultaneous measurements allow us to evaluate the latent heat accurately. Latent heat decreases with field and the value of critical electric field --that where latent heat disappears-- is estimated to be (0.44\pm0.03) kV/cm. Incidentally, we have measured simultaneously the dielectric permittivity which suggests that latent heat is developed as domains are growing. 
Jose-Maria Delgado-Sanchez, Jose-Maria Martin-Olalla, Maria-Carmen   Gallardo, Saturio Ramos, Marceli Koralewski and Jaime d...