Electronics Letters
Electronics Letters > 1986 > 22 > 12 > 671 - 672
Electronics Letters > 1990 > 26 > 20 > 1734 - 1736
Electronics Letters > 1992 > 28 > 1 > 44 - 46
Electronics Letters > 1992 > 28 > 7 > 645 - 647
Electronics Letters > 1992 > 28 > 20 > 1902 - 1904