TY - JOUR A1 - Wegener, Michael A1 - Wirges, Werner A1 - Richter, Kristin A1 - Künstler, Wolfgang A1 - Gerhard, Reimund T1 - Charge stability and piezoelectric properties of porous fluoro-polymer space-charge electrets in layer systems Y1 - 2001 ER - TY - JOUR A1 - Wegener, Michael A1 - Künstler, Wolfgang A1 - Richter, Kristin A1 - Gerhard, Reimund T1 - Ferroelectric polarization in stretched piezo- and pyroelectric poly(vinylidene fluoride-hexafluoropropylene) copolymer films Y1 - 2002 ER -