Electronics Letters
Electronics Letters > 1990 > 26 > 10 > 649 - 651
Electronics Letters > 1990 > 26 > 10 > 634 - 635
Electronics Letters > 1992 > 28 > 2 > 111 - 113
Electronics Letters > 1992 > 28 > 14 > 1361 - 1362
Electronics Letters > 1993 > 29 > 4 > 351 - 352