(;
AB[ch][dp][gq][cq]
AW[cj][cm][bp]
C[Black plays.

Source:  "Tesuji", Ch. 2, pp. 38-39,
         James Davies, Ishi Press];
B[bn]
C[A tesuji worth remembering.]
(;
W[cn]
C[White almost invariably gives up
the corner stone to keep sente.];
B[bo];
W[co];
B[cp];
W[bm];
B[bq]
C[Black has gained quite a few points.
But usually in the opening, even such a large
capture as this is not worth losing sente.]
)
    (;
    W[co]
    C[If White tries to cut off Black...];
    B[cn];
    W[dn];
    B[bm];
    W[cl];
    B[bo];
    W[cp];
    B[do];
    W[bq];
    B[en];
    W[dm];
    B[br]
    LB[cr:a]
    C[Black should not descend to A, otherwise
White will descend to 13 and win the semeai.

But with 13, Black captures the White stones.
Not convinced yet?
Play on...];
    W[cr];
    B[dq];
    W[ar];
    B[bs];
    W[cs];
    B[ap];
    W[as];
    B[br];
    W[bs];
    B[ao]
    C[And White runs out of liberties
before Black.]
    )
)
