According to sources that really treat the question - and by that I eliminate sources which merely state 'was impeached/ousted by a vote of 328 - 0' - in some detail, the vote was not legal. See here . The wording is 'politically correct', i.e. they do not explicitly say the vote was null and void, what they do however is to list some of the provisions that were not followed. Now, the idea that 'Most reliable English-language sources state that Yanukovych is impeached.' But one could equally start counting Russian sources that say exactly the opposite! It all boils down to which sources treat an issue in necessarily thorough manner. I have not seen a single source yet that claims the impeachment was done according to this and that provision effective at the moment. One English language source - linked here - does treat this question and indeed points out that this was not the case and points out shortcomings (to use an euphemism). Wikipedia is not a democracy. One good source can trump ten sloppy/partisan sources.