107-Problem Solution.

Solution: 1. Qf6! threatening [2. Qe6, Be6#]
 1. ... Rb6+ 2. Sxb6#
 1. ... Rxd6 2. Qxd6#
 1. ... Rxc5+ 2. Rxc5#
 1. ... Bxe3 2. Be6#
 1. ... Sg5/d4+ 2. Q(x)d4#
 A Threat problem that includes three crosschecks