1. Sc3! Kc2 2. Sxa2 Lxa2 3. Lxa2 Kd3 4. 0-0-0#
1. ... Kxb2 2. Sxb1+ Kc1,Kc2 3. Sa3#

" I may, through lack of attention, have created a awkward problem for the composers. They do care a lot, and rightly so, about precedence, anticipation, novelty of idea & setting.
Between sending me his first Belén problem on 17 July and my publication of it on 24 July, Pérez Carballo also sent me a gamefile with games of his, and at the end two "Belén Theme" four-movers, the second being a new version which I must admit did not really take root in my mind.
Right after my publication of the Belén problem, Michael McDowell sent me the two three-movers above and the next day, the four-move version with 1.Nd1!
As it turns out now however, that other four-mover in Pérez Carballo's gamefile anticipates, to a degree, McDowell's 1.Nd1 four-mover.

(diagram)

Largely the same setting and the same play. There can be no doubt that McDowell's problem is better (at the Chess Problem Discussion Board Pérez Carballo recognizes that) but there is also no doubt Pérez Carballo had some of the ideas first - of course without McDowell knowing that. Still, an anticipation. But: is an anticipation an anticipation without publication? Have I wronged somebody and if so, whom?
I'm afraid all I can do is turn beet-red, and thank both composers for their work. The Belén Theme Story amounts to an interesting insight into the development of a problem idea."