1. V. L. Bondarenko and Yu. M. Simonenko, Cryogenic Technologies of Rare Gases Extraction, Astroprint, Odessa (2014).
2. E. Obukhova, “Noble gases bring millions,” Ekspert Online (2017); http://expert.ru/2017/04/4/millionyi%2D%2Dv-vozduhe.
3. V. L. Bondarenko, N. P. Losyakov, Yu. M. Simonenko, et al., “New technologies for the recovery of rare gas concentrates,” Tekh. Gazy, No. 1, 42–52 (2011).
4. John A. Jensvold, Membrane for Separation of Xenon from Oxygen and Nitrogen and Method of Using Same, U.S. Patent No. 6168649, Int. Cl. 62/74 (2001).
5. A. V. Oleinik, V. S. Oleinik, and V. P. Sedov, Method for Extracting Krypton and Xenon from Process Waste Gases, Russian Patent No. RU2150758C1 (2000).