Please check the webpage at my former university for older publications as well. Feel free to contact me per E-mail, if you wish to obtain a PDF version of a paper not linked here or check out one of the following links:
Iruru Ouchi, Mayu Horiuchi, Ferdinand Peper, Kenji Leibnitz, Naoki Wakamiya, Maki Arai, Jin Nakazato, Mikio Hasegawa, "Feasibility Study of Asynchronous Pulse Code Multiple Access for Underwater VLF Communication", submitted for publication.
The papers marked as "in preparation" are currently work in progress or only intended publications and the given titles are tentative.