Samoylov, Boris (1 February 2012). "Загадка первомая 1960 года – часть I" [Riddle of May Day 1960 – Part I]. Военно-промышленный курьер (Military-Industrial Courier, VPK) (به روسی). Archived from the original on 25 July 2020. Retrieved 21 May 2013.
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Samoylov, Boris (1 February 2012). "Загадка первомая 1960 года – часть I" [Riddle of May Day 1960 – Part I]. Военно-промышленный курьер (Military-Industrial Courier, VPK) (به روسی). Archived from the original on 25 July 2020. Retrieved 21 May 2013.