Tsumego from my match with Pyro

PyroGX (19k) is one of those players whose games I like to watch. I know he reads deeper than I do and I've seen him execute some very impressive plays. I was very fortunate have a match with him this evening in a game rated at 22k (3-stone handicap). I won by only 5.5 moku owing to an aggressive territorial reduction which established a living group in the center of the board.

But the immediate post-game analysis by yoyoma (3k) revealed a very interesting situation in the lower-right corner of the board where black could have captured a group of white stones and created life. Both Pyro and I assumed that the nine black stones were all dead. The analysis begins at move 237 in the SGF file (first branch) but, for those of you who would like to test yourselves, I'm presenting it below as a tsumego. My understanding was that, among the observers, only yoyoma saw it.

Black to move and capture the R6 group.
For simplification, assume that White cannot make an
effective ko threat.

In other news, I found some interesting Go curios on eBay this evening. They look like old Japanese Go books and may be more suitable as conversation pieces than articles for study. You can see them at auctions 7716259343, 7716260176 and 7716261558.