Reference 19

D. L. Voronov, E. H. Anderson, R. Cambie, L. I. Goray, P. Gawlitza, E. M.Gullikson, F. Salmassi, T. Warwick, V. V. Yashchuk, H. A. Padmore, “Development of near atomically perfect diffraction gratings for EUV and soft x-rays with very high efficiency and resolving power,” Journal of Physics: Conference Series C, vol. 425, 2013, pp. 152006-1–4.

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