(;
AB[jq][nq][ep][gp][np][io][dn][gn][dm][cl]
AW[dq][fq][gq][hq][oq][pp][co][cn][pn]
C[Black plays.

Source:  Tesuji Dictionary, Vol. 1, Tsuke #55,
Segoe Kensaku & Go Seigen, Ishi Press]

(;
B[dp]
C[Vulgar.

Black misses a huge opportunity.];
W[cq]
C[White finds the key defensive move.
Black can no longer cause trouble
in the corner.];
B[cp];
W[bp];
B[eq];
W[er];
B[bq];
W[bo];
B[br];
W[cr]
C[And White is safe.]
)
    (;
    B[dr]
    C[Correct.
A sparkling tesuji.

White cannot avoid an outright
loss on the left or bottom side, or
a huge ko for the majority of White's
corner terrritory.]
    (;
    W[cq]
    C[Now the key point at 2 no longer
works for White.];
    B[eq]
    C[And Black takes the bottom edge.]
    )
        (;
        W[cr]
        C[Again, White cannot avoid an
outright loss on the left or bottom.

For example...];
        B[cq];
        W[er];
        B[dp];
        W[ds];
        B[cp]
        )
        (;
        W[er]
        C[Gives Black a one-sided ko in the corner.
But as a small consolation, White can take the ko first.];
        B[cq];
        W[dp];
        B[br];
        W[ds];
        B[cs]
        )
        (;
        W[eq]
        C[White 2 allows Black to live
outright in the corner.];
        B[cq];
        W[dp];
        B[br];
        W[bp];
        B[bq]
        )
    )
)
