In this violin sheet I'm trying to play, why are there two numbers above this note?

Can you scan a bit more of the context?

Okay, that's what I thought. The top numbers are a fingering indication. You play the B with the second finger and quickly slide up to the G harmonic on the same finger. In more advanced music, the 0 almost always indicates a harmonic, unless the composer specifically wants you to use an open string for some reason. Only beginner music tells you which fingers to use for every note. The 30 is a bar number.

If you can't interpret that fingering you probably shouldn't be trying to play that piece. If you haven't built up the necessary technical background you're likely to give yourself permanent hand injuries.

The numbers above the notes are probably fingerings, numbering the index through pinky, 1 through 4, with 0 open (though that doesn't make sense to me on that note). The number below the notes is probably a measure number, the 30th measure of the piece.

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