Capturing the L-group

The L-group is dead, in the ideal situation where the outside group is alive and no neighbouring stones come to rescue. However, actual play is rarely ideal or clear-cut and the surrounding group may be short of liberties itself. Post your game positions here where the attacker was forced to capture the L-group.

• Tsumego From Games 18 - something that looks very similar to the L-group but cannot be captured.
• Tsumego From Games 19 - some elements of the L-group can be found.
• Kyu Exercise 90 - application problem.