Shikatsu Myoki Tsumego Series 76 / Solution

Original Solution  

Note: In Shusai's days, local ko threats must be considered in solving a composed problem. Black has none after .

Continued  

Live in double ko.

Reference  

In practice, Black may use an outside ko threat and capture the ko at . After , it's still a double ko.

Reference 2  

can't prevent the double ko or escape to the left. (Of course, White uses these moves as ko threats to capture the ko in the right.)