PDF Download Schedule 1 [Fr-E-58] Ultrasonic Investigation of Triangular-Lattice-Antiferromagnet YbCuGe *Koji Araki1, Nobuyoshi Ouchi1, Ryuji Ueda1, Isao Ishii2, Takashi Suzuki2, Akira Ochiai3, Kenichi Katoh1 (1. National Defense Academy(Japan), 2. Hiroshima University(Japan), 3. Tohoku University(Japan)) Keywords:frustration, ultrasound