L. Pagani, C. Lefèvre, M. Juvela, V. Pelkonen, and F. Schuller. (2015)cite arxiv:1501.00861Comment: Letter to A&A (accepted for publication). must be viewed with ACROBAT READER for full enhancement. Otherwise, check images in Appendix A.
F. Vogt, M. Dopita, L. Kewley, R. Sutherland, J. Scharwaechter, H. Basurah, A. Ali, and M. Amer. (2014)cite arxiv:1406.5186Comment: 21 pages, 15 figures, accepted for publication in ApJ. Due to size limitations, the supplementary STL file for the 3D-printable diagram is available here: http://www.mso.anu.edu.au/~fvogt/online_material.html.