Azerbaijan’s opposition is contesting the results of a referendum that lifts a limit on how long someone can be President. The outcome gives Ilham Aliyev the chance to extend his rule over the former Soviet nation, which is also a top oil-producing state.Officials say more than 90 percent of voters backed the changes. One voter said: “Excellent. We are all happy. We all participated in this referendum and we want our President to stay in power for a lifetime.” But the opposition disputes claims that the vote was free and fair, although it has stopped short of calling for street protests against Aliyev. The President’s second term is due to end in 2013, but the referendum result means he can now seek further terms. The opposition says its monitors witnessed what it calls thousands of voting violations. It also disputes the official turnout figure of 71 percent, saying it does not believe it reached the 25 percent mark needed for the result to be valid. The government rejects the criticism. A delegation from the Council of Europe commended the way the ballot was carried out. However, the rights body says the country could enhance democracy by moving some power away from the President to the parliament.