(;
AB[cf][pd][pc][nd][mc][rf][qg][qi][pi][oi][rk][ql][qo][ro][pq][mp][ep][fq][gp]
AW[dd][kc][nc][qe][pf][pg][ph][qh][nf][mh][mk][ok][qk][qn][cp][dq][eq][dn][fk][rh]
C[Black's response to White's marked play?

Source:
    "Go World" #33,  Autumn 1983, pp. 56-57
    China-Japan Go Exchange
    Ma Xiaochun  vs.  Kobayashi Koichi]
TR[rh]
(;
B[rc]
C[The only move.
Black cannot ignore the defense
of the corner.
The game continued...];
W[pl];
B[qj];
W[pk];
B[rm];
W[jp]
C[And White has time to erase Black's moyo.]
)
    (;
    B[]
    C[If Black ignores the upper right corner...];
    W[nb]
    C[White exposes Black's corner weakness.]
    (;
    B[mb];
    W[md];
    B[oc];
    W[ne];
    B[od];
    W[lc];
    B[ob]
    C[And White's outside thickness is
painful for Black.]
    )
        (;
        B[lc]
        C[If Black tries to resist...];
        W[od];
        B[md];
        W[oc];
        B[oe];
        W[pe];
        B[ne];
        W[pb]
        C[And Black's corner collapses.]
        )
    )
)
