Issue 68 of the German magazine Problem Forum (study section) December 2016.

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Studies in this article:

[Event "E220 1.p Pat a Mat#780"] [Site ""] [Date "2014"] [Round ""] [White "Slumstrup Nielsen=S"] [Black "(+0441.00f2d3)"] [Result "1/2-1/2"] [SetUp "1"] [FEN "8/1B1N4/8/1b6/2R5/3kr3/5K2/8 w - - 0 1"] [PlyCount "13"] [EventDate "2014"] 
 {Pat a Mat/12} 1. Rb4 (1. Rc5 $2 Re2+ 2. Kf3 (2. Kf1 Re7 3. Ne5+ Kd4+ 4. Rxb5 Rxe5) 2... Re3+ 3. Kf4 Bxd7 4. Ba6+ Bb5 $1 5. Bxb5+ Kd2 6. Rd5+ Ke1 7. Kxe3) ( 1. Rc7 $2 Re2+ 2. Kf3 Re3+ 3. Kf4 Bxd7 4. Ba6+ Kd2 5. Rxd7+ Ke1 6. Kxe3) 1... Re2+ (1... Bxd7 2. Rb3+) (1... Re7 2. Nc5+ Kc3 3. Rxb5 Kc4 4. Ba6 Re5 5. Nd3) 2. Kf1 (2. Kf3 $2 Bxd7 3. Ba6+ Bb5 $1 4. Bxb5+ Kc3 5. Rc4+ Kd2 6. Rd4+ Ke1 7. Bxe2) 2... Re7 (2... Bxd7 3. Ba6+ Kc3 (3... Bb5 4. Bxb5+ Kc3 5. Rc4+ Kd2 6. Rd4+ Ke3 7. Rd3+ Ke4 8. Kxe2) 4. Rc4+ Kd2 5. Rd4+ Ke3 6. Rd3+ Ke4 7. Kxe2) 3. Nc5+ Kc3+ 4. Rxb5 Kc4 (4... Rf7+ 5. Kg2 Kc4 6. Ba6 Rf5 7. Ra5+ Kb4 8. Ra4+ Kxc5 9. Ra5+ Kb6 10. Rxf5) 5. Ba6 (5. Ra5 $2 Kb4) 5... Re5 6. Nd3 $1 (6. Nb7 $2 Rxb5 7. Nd6+ Kc5 8. Nxb5 Kb6) (6. Ne6 $2 Rxb5 7. Nc7 Kc5 8. Nxb5 (8. Bxb5 Kb6) 8... Kb6) (6. Ra5+ $2 Kb4 7. Rb5+ Kc4) 6... Rxb5 7. Ke2 1/2-1/2