, ▁inter views , ▁letters ▁▁▁▁▁▁▁▁▁▁▁▁▁▁ ▁( public ly ▁available ▁un ab rid ged ▁Russian ▁text ) ▁▁ ▁( public ly ▁available ▁un ab rid ged ▁Russian ▁text ) ▁▁▁▁ ▁( public ly ▁available ▁un ab rid ged ▁Russian ▁text ) ▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁ ▁▁▁▁ ▁( public ly ▁available ▁un ab rid ged ▁Russian ▁text ) ▁ ▁Further ▁reading ▁ ▁Video ▁ ▁References ▁ ▁External ▁links ▁ ▁Spe ech ▁of ▁Pet ro ▁Gr ig oren ko ▁to ▁Crime an ▁Tat ars , ▁ 1 9 6 8 ▁ ▁Pet ro ▁G . ▁Gr ig oren ko ▁- ▁Review ▁of ▁a ▁life ▁and ▁a ▁book ▁ ▁General ▁Pet ro ▁Gr ig oren ko ▁Foundation ▁- ▁English , ▁Russian , ▁Ukrain ian ▁▁ ▁( The ▁bi ography ▁of ▁Gr ig oren ko ▁on ▁the ▁website ▁of ▁the ▁Moscow ▁Hels ink i ▁Group ) ▁▁ ▁( The ▁bi ography ▁of ▁Gr ig oren ko ▁on ▁the ▁website ▁of ▁the ▁Online ▁Library ▁of ▁Alexander ▁Bel ous en ko ) ▁▁ ▁( The ▁bi ography ▁of ▁Gr ig oren ko ▁on ▁the ▁website ▁of ▁the ▁And rei ▁Sak har ov ▁Museum ▁and ▁Public ▁Center ) ▁ ▁Category : 1 9 0 7 ▁birth s ▁Category : 1 9 8 7 ▁death s ▁Category : Pe ople ▁from ▁Bor is ov ka , ▁P ry mor sk ▁Ra ion ▁Category : Pe ople ▁from ▁T aur ida ▁Governor ate ▁Category : K h ark iv ▁Poly techn ic ▁Institute ▁al umn i ▁Category : Mil it ary ▁Engineering - Te chn