(;
AB[cq][hq][bp][cp][dp][ep][fp][hp][mp][np][op][pp][qp][co][fo][ho][io][jo][ko][lo][cn][kn][cm]
AW[br][cr][hr][bq][dq][eq][fq][gq][iq][lq][ip][lp][mo][no][oo][dn][ln][qn][bm][dm][fm][hm][jm][km][mm][cl][bk][dk]
C[Black plays.
Source:  Tesuji Dictionary, Vol. 1, Tsuke #21,
Segoe Kensaku & Go Seigen, Ishi Press]
(;
B[kq]C[Best.  Black cuts off part of White's group.];
W[kr];
B[jr]
(;
W[ir];
B[jq]
)
    (;
    W[kp];
    B[ir]
    )
)
    (;
    B[kr]
    C[Fails];
    W[kq]C[Black can no longer cut off the White stones.]
    (;
    B[jr];
    W[ir]
    )
        (;
        B[jq];
        W[jp];
        B[jr];
        W[ir]
        )
    )
)
