Checkmate in 2

A challenging puzzle, testing your patience and spirit of observation. Please email me your solutions or post them as comments. You need to have a website account to be able to post comments.

[Event "Study by Alberto Armeni"][Date "1981.??.??"][Result "1-0"][FEN "8/2P1pR2/1KPk4/2N1r3/2P3b1/8/7B/8 w - - 0 1"]