Endgame Technique: Undermining The Bishop

[Event "?"]
[Site "?"]
[Date "1930.??.??"]
[Round "?"]
[White "Heuäcker, P."]
[Black "?"]
[TimeControl "-"]
[Result "1-0"]
[Annotator "Aagaard/Lund"]
[ECO " "]
[Setup "1"]
[FEN "1B6/8/7P/4p3/3b3k/8/8/2K5 w - - 0 1"]

1.Ba7 Ba1 2.Kb1 Bc3 3.Kc2 Ba1 4.Bd4 Bxd4 5.Kd3 Kg5 6.h7 Ba1 7.Ke4 1-0