1. Nishii, K., Inoue, K., Matsuno, T., and Tezuka, A.: ‘High-performance AlGaAs/GaAs/AlGaAs selectively doped double-heterojunction FET and its application to digital ICs’, Rupprecht, H., Christou, A., Gallium arsenide and related compounds, (Institute of Physics, London 1987), p. 657–660