Is This Really A Draw?

Spanton (1881) - Paul Vlkovic (1833), Olomouc seniors round nine

Black has just played 59...Rb2-d2 and offered a draw

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The answer seems to be: yes, it really is a draw
Both my main analysis engines, Stockfish10 and Komodo9, reckon Black is winning. Stockfish10 has Black at +3.42 pawns; Komodo9 at +2.24 pawns.
But as long as White keeps his rook protecting the f pawn, and threatens the bishop when possible, there seems no way for Black to make progress.
The engines try various manoeuvres, but nothing significantly changes, including the advantage they reckon Black has. That last point is often a tell-tale sign a position is drawn - otherwise the evaluation would change as one side improves its position.
My final score of +4=3-2 saw me gain 7.4 Fide elo. I came third-through-seventh - fourth on tiebreak.