Similar keys, exercise

Dear readers, if you are ready to try your solving skills, we present here three problems, with a common characteristic in the key move. (If you find any difficulty, see again the problem-9).
You will find the solutions at the end of this post.

	(Problem 23) Ph. Klett ”Schachprobleme”, 1878 White plays and mates in 2 moves #2 (7+5)
[8/6p1/4P1P1/4KpPk/5BSp/7p/8/1Q6]

	(Problem 24) R. Sutherland, ”Sunday Times”, 1966, Special Mention BCPS (British Chess Problems Society) Ring Tourney, 1966 White plays and mates in 2 moves #2 (14+8)
[3BBbR1/4PPrs/2S1PPkq/2KpPSrb/5RPQ/8/8/8]

	(Problem 25) Jacques Fulpius Schweizerische Schachzeitung, 1968 White plays and mates in 2 moves #2 (10+5)
[8/8/3P1B2/1BSPpK2/1Ppp4/k7/SR4Q1/b7]

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Solution of the problems
These three problems are similar because their keys have the same characteristic: en-passant capture.

Problem 23 (Ph. Klett) #2
Key: 1.gxf6 e.p.!
1...gxf6+ 2.Sxf6#
1...Kxg4 2.Qd1#

Problem 24 (R. Sutherland) #2
Key: 1.exd6 e.p.!
1...Rxf5+ 2.gxf5#
1...Rxg4 2.Se5#
1...Bxg4 2.Qxh6#
1...Sxf6 2.exf8=S#
1...Rxg8 2.fxg8=S#
1...Rxf7 2.exf8=S#
1...Bxe7 2.Sfxe7#

Problem 25 (Jacques Fulpius) #2
Key: 1.dxe6 e.p.!
1...Bxb2 / d3 2.Qa8#
1...c3 2.Rb3#

[This post in Greek language].