A 30- mu A data-retention pseudostatic RAM with virtually static RAM mode. - Kazuhiro Sawada; Takayasu Sakurai; Kazutaka Nogami; Katsuhiko Sato; Tsukasa Shirotori; Masakazu Kakuma; Shigeru Morita; Masaaki Kinugawa; Tetsuya Asami; Kazuhito Narita; Jun-Ichi Matsunaga; Akira Higuchi; et al. (IEEE J. Solid State Circuits, 1988)