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Comment: 12 pages, Latex, 2 Maple graphs available from authors; submitted ApJ.
A. Rakic, D. Simon, J. Adamek, and J. Niemeyer. (2009)cite arxiv:0911.3910
Comment: 4 pages, 2 figures, proceedings (Annalen der Physik) of the
Grassmannian Conference in Fundamental Cosmology (Grasscosmofun'09) Szczecin,
Poland, 14-19 September 2009.
M. Célérier, K. Bolejko, and A. Krasiński. (2009)cite arxiv:0906.0905
Comment: 25 pages, 20 figures, substantially revised to match the published
version, figs. 9 and 19 changed to match the captions.