The following publications are possibly variants of this publication:
- Asymptotic Upper Bounds on the Minimum Distance of Trellis CodesA. Robert Calderbank, James E. Mazo, Victor K. Wei. tcom, 33(4):305-309, 1985. [doi]
- Sphere-packing upper bounds on the free distance of trellis codesGregory J. Pottie, Desmond P. Taylor. TIT, 34(3):435-447, 1988.
- Upper bounds for small trellis codesA. Robert Calderbank, Gregory J. Pottie. TIT, 38(6):1791, 1992.