51. 2014 年 2 月 28 日乌克兰常驻联合国代表给安全理事会主席的信(S/2014/136)(2014 年 2 月 28 日；2015 年 2 月 27 日)。
51. Letter dated 28 February 2014 from the Permanent Representative of Ukraine to the United Nations addressed to the President of the Security Council (S/2014/136) (28 February 2014; 27 February 2015).