Y. Izotov, G. Stasinska, and N. Guseva. (2013)cite arxiv:1308.2100Comment: 23 pages, 14 figures, accepted for publication in Astronomy and Astrophysics.
M. Pettini, and R. Cooke. (2012)cite arxiv:1205.3785Comment: 10 pages, 7 figures, Submitted for publication in Monthly Notices of the Royal Astronomical Society.