1. Basovich SN, Sergeev PV, Strelkov RB. Breathing device for hypoxia creation. Inventors certificate 1335294, A61M 16/00. Patent USSR, 07.09.87. Bulletin # 33; 1987 [In Russian].
2. Bassovitch O. Breathing apparatus for hypoxic pre-acclimatization and training. Patent Application Publication US 2006/0130639 A1, A62B 7/10, A62B 23/02. 22 June 2006.
3. Berezovski VA, Deinega VG, Zhuravlenko VJa et al. Device for climatotherapy. Inventors certificate 1526688, A 61 G, 10/00 Patent USSR, 7 Dec 1989. Bulletin #45; 1989 [In Russian].
4. Berezovski VA, Levashov MI. Introduction in orotherapy. Kiev: APG; 2000 [In Russian].
5. Berezovski VA, Rozhanchuk VN, Puh NN et al. Equipment for climatotherapy. Inventors certificate 1801440, A61G 10/00. 15 Mar 1993. Bulletin #10; 1993 [In Russian].