According to whom was Yuri Izrael the  "most influential scientific adviser" to the current President of Russia?
Yuri Izrael Yuri Antonovich Izrael (Russian: Юрий Антониевич Израэль ; 15 May 1930, Tashkent – 23 January 2014, Moscow) was a vice-chairman of the Intergovernmental Panel on Climate Change (IPCC) until September 2008, when the new bureau was elected. He was the "most influential scientific adviser" for Vladimir Putin, the former president of Russia, according to CNN.
Valery Petrosyan Valery Samsonovich Petrosyan (Russian: Валерий Самсонович Петросян ; born March 7, 1942 in Baku) is a Professor, Doctor of Chemical Sciences, academic and member of Presidium of RAEN. From 2008 to 2010 he was a UN expert of chemical security. Deputy chairman of Supreme ecological council of Russia (1990—1996). Foreign Member of Armenian National Academy of Sciences.