Criterion for the membership of individual meteors to meteoroid streams presented by Valsecchi {\it et. al.} (1999) and Jopek {\it et. al.} (1999) is discussed. The authors characterize and use their criterion as a distance function. However, it is not a distance function. Some practical aspects are also discussed. Correct criterion is presented.
Cite
@article{arxiv.astro-ph/9910046,
title = {On Meteoroid Streams Identification},
author = {Jozef Klacka},
journal= {arXiv preprint arXiv:astro-ph/9910046},
year = {2007}
}