We reply to the criticism of Opthof and Leydesdorff [arXiv:1002.2769] on the way in which our institute applies journal and field normalizations to citation counts. We point out why we believe most of the criticism is unjustified, but we also indicate where we think Opthof and Leydesdorff raise a valid point.
@article{arxiv.1003.2113,
title = {Rivals for the crown: Reply to Opthof and Leydesdorff},
author = {Anthony F. J. van Raan and Thed N. van Leeuwen and Martijn S. Visser and Nees Jan van Eck and Ludo Waltman},
journal= {arXiv preprint arXiv:1003.2113},
year = {2010}
}