Given a document, find the main entity about whom the author is writing. Write the full name if mentioned in the text. Note that URLs in the text have been replaced with [Link].
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Question: “Without the reference to a June review  Russia would have been tied to the end of 2018; it wanted instead to have an escape clause ”  Petromatrix strategist Olivier Jakob  said.
“It leaves a question mark about the second half [of 2018] and about the commitment of Russian oil companies  which will be price dependent ”  he  said.
The CEO of Russia’s top private producer Lukoil told Reuters  he  would like to see the price of oil stable at current levels  trading in the $60-65 per barrel range.
The oil market is unlikely to overheat   he  added  thanks to cooperation between OPEC and its allies which would allow them to release new output into the market to rebalance it.

Answer: Olivier Jakob


Question: Sportscaster Dick Enberg  Whose Career Spanned 60 Years  Dies At 82
 Legendary announcer Dick Enberg   whose amazing sportscasting career spanned six decades  died Thursday at the age of 82. He did play-by-play for college basketball  college and professional football and Major League Baseball. He also called other sporting events such as boxing  tennis  golf  horse racing and the Olympics.
 Enberg  retired from  his  TV job with the San Diego Padres in October 2016.
The team released a statement on  Enberg 's death:
"We are immensely saddened by the sudden and unexpected passing of  legendary broadcaster Dick Enberg .  Dick  was an institution in the industry for 60 years and we were lucky enough to have  his  iconic voice behind the microphone for Padres games for nearly a decade. On behalf of our entire organization  we send our deepest condolences to his wife  Barbara  and the entire  Enberg  family."
Endberg was known for exclaiming "Oh my!" So much so  that his 2004 autobiography is titled: Dick Enberg  Oh My!
 Enberg 's big break came when he was chosen to call UCLA basketball games. During that nine-year stint  the Bruins won eight NCAA titles.
When asked what was the most historically important event he covered   Enberg  replied  "The Game of the Century." In that 1968 game  the University of Houston Cougars beat UCLA to snap the Bruin's 47-game winning streak.
During his time behind the microphone  Enberg  had many broadcast partners  including Al McGuire  Merlin Olsen and Don Drysdale.
 Enberg 's wife Barbara told the San Diego Union-Tribune that her husband died Thursday morning at his home in La Jolla  Calif.
"Barbara Enberg said the family found out later in the day when  Dick Enberg  failed to get off a flight in Boston  where they were scheduled to meet. She said her husband had appeared to be waiting for a car that was set to shuttle him to the San Diego airport for a 6:30 a.m. flight. " 'He was dressed with his bags packed at the door ' she said. 'We think it was a heart attack.' "

Answer: Dick Enberg


Question: Russian Bobsled Federation president Alexander Zubkov told The Associated Press on Friday that a drug-test sample that  pilot Nadezhda Sergeeva  gave on Sunday was positive.
" She  confirms  she  took no such medication and the team confirms  she  was not issued any medication " said Zubkov  a former bobsledder who himself was stripped of two Olympic gold medals for the Russian doping scheme at the 2014 Sochi Games. "Federation representatives at the Olympics" are starting to prepare a defense  he said.
Zubkov also said a sample  she  had given five days earlier was negative.
 Nadezhda Sergeeva  (right) has tested positive for trimetazdine  which is listed as a banned substance by the World Anti-Doping Agency.
 Sergeeva 's crew finished 12th in the women's bobsled competition on Wednesday  after she had given the sample that later came back positive.
Earlier this month   Sergeeva  told the AP that competitors from other countries had warmed to her after she passed IOC vetting for Pyeongchang  which included an examination of her drug-testing history.
"I don't know why  but they've started talking to us more than ever before. I feel it. Maybe it's a sign to them that we're clean  " Sergeeva  said. "There's a lot of people coming up and saying  'We're happy you're here.'"
At the time  she was training in a T-shirt with the words "I Don't Do Doping."  Sergeeva  used to compete in track and field as a heptathlete before switching sports in 2010.
 Sergeeva  switched to driving a bobsled after competing in track and field as a heptathlete.
Trimetazidine  the substance found in  Sergeeva 's sample  has been detected in previous doping cases. Chinese swimmer Sun Yang  an Olympic gold medalist  was banned for three months in 2014 by his country's sports authorities after testing positive for the substance.

Answer:
Nadezhda Sergeeva