With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Water prevails at standard ambient temperature and pressure, but also has other states
text_B: Ruslan Grigorievich Skrynnikov -LRB- Руслан Григорьевич Скрынников ; 8 January 1931 , Kutaisi , Georgian SSR , -- 16 June 2009 , St. Petersburg , Russia -RRB- was a Russian historian who studied the reign of Ivan the Terrible .. Kutaisi. Kutaisi. Georgian SSR. Georgian SSR. St. Petersburg. St. Petersburg. Russia. Russia. historian. historian. Ivan the Terrible. Ivan the Terrible. He later moved on to study the Time of Troubles .. Time of Troubles. Time of Troubles. For Skrynnikov , control over the bureaucratic apparatus -LRB- rather than the issue of centralization -RRB- was the primary point of contention explaining Muscovite political struggles of the 15th and 16th centuries .. bureaucratic. bureaucracy. In the late 1960s he described Ivan 's Oprichnina as the reign of terror designed to root out every possible challenge to the autocracy  :. Oprichnina. Oprichnina. Skrynnikov ' monographs about the Oprichinina and the Russian conquest of Siberia have been reprinted many times and translated into other major languages .. Russian conquest of Siberia. Russian conquest of Siberia. He also authored the biographies of Ivan III , Ivan IV , and other Russian tsars .. Ivan III. Ivan III
not_related.