Author,Title,Journal,ISSN,Publisher,Date,Volume,Number,Page,URL,URL(DOI) 山下 崇博 and 竹下 俊弘 and 大内 篤 and 小林 健,Ultrathin Piezoelectric Loudspeaker – Flexible Film Loudspeaker -,Proceedings of JIEP Annual Meeting,,The Japan Institute of Electronics Packaging,2021,35,0,19A2-03,https://cir.nii.ac.jp/crid/1390854717781946496,https://doi.org/10.11486/ejisso.35.0_19a2-03