SEARCH Articles Figures Tables Oriented Polyethylene Terephthalate Sheet with Orthorhombic Symmetry Orthorhombic Orthorhombic Pbnm symmetry Orthorhombic cell/crystal/symmetry Orthorhombic symmetries, ferroelectrics Polyethylene terephthalate orthorhombic symmetry The Elastic Constants for Specimens Possessing Orthorhombic Symmetry