1. L. Bary-Soroker and N. D. Tan, On p-embedding problems in characteristic p, Journal of Pure and Applied Algebra 215 (2011), 2533–2537.
2. J. W. S. Cassels and A. Fröhlich, Algebraic Number Theory, Academic Press, London, 1967.
3. B. Conrad, O. Gabber and G. Prasad, Pseudo-reductive groups, Series: New Mathematical Monographs (No. 17), Cambridge University Press, Cambridge, 2010.
4. S. Durhan, Additive polynomials over perfect fields, available at: http://math.ncc.metu.edu.tr/content/files/azgin/addpol.pdf
5. I. Efrat, Valuations, Orderings, and Milnor K-theory, Mathematical Surveys and Monographs 124, American Mathematical Society, Providence, RI, 2006.