A black piece gives check and unpins a white piece which defeats the check giving check.
See also: Authier theme.
Visserman, Eeltje
Al Hamishmar, Israel Ring Tourney, 1964
6th Prize
a) 1.Bxd5+
Kxd6
2.Be6+
Bxd3#
b) 1.Rxg6+
Kf7
2.Re6+
Rxh5#
Niemann, John
Feenschach, 1963 (corr.)
2nd Prize
1.Sd5
Bb6
2.Sf4+
Sd5
3.Sg2+
Sef4#