Boris Nikolaevich Nazarov and LI Sokolov
The Problemist, 1972
Mate in 2
(b) wQf7->f2
(a) KEY: 1.Ra6!
(b) COOK: 1.Rf7!
José Antonio Coello
Correction
Mate in 2
(b) wSf7->f2 & bPg7->e7