I'm very surprised (well, not really) to read so many complaints about this somehow being an attempt to annul the vote. Nobody voted for the executive to trigger Article 50 without reference to Parliament. And nobody voted for our democracy to stop being a Parliamentary one either. Neither option was on the ballot paper, contrary to what some appear to believe.
If you choose to vote Leave without anyone having set out any mechanism as to how this might be accomplished, well that's the risk you take. Democracy innit.