Electronics Letters
Electronics Letters > 1990 > 26 > 22 > 1857 - 1858
Electronics Letters > 1991 > 27 > 8 > 662 - 664
Electronics Letters > 1991 > 27 > 8 > 636 - 637
Electronics Letters > 1991 > 27 > 25 > 2389 - 2391
Electronics Letters > 1992 > 28 > 7 > 690 - 692