(;
AB[cd][ed][ic][qn][pj][pd]
AW[dg][dj][dp][pp][nq]
C[White plays.

"Go World", #32, Summer 1983, pp. 24-25
Kato Masao vs. Cho Chikun
21st Judan Title, game 4
Okubo Ichigen commentary.]
TR[pj]
(;
W[nc]
C[Inferior.
The ordinary approach move
doesn't work here.];
B[oc];
W[nd];
B[pf];
W[kc];
B[ie]
TR[ic]
C[And White has a cramped position
because of the marked Black stone.]
)
    (;
    W[qc]
    C[Correct.
This invasion may seem a little
early, but see the variation for
approaching from the outside.]
    (;
    B[qd]
    C[The correct response.];
    W[pc];
    B[oc];
    W[ob];
    B[nc];
    W[nb];
    B[mc];
    W[mb];
    B[lc];
    W[rd];
    B[re];
    W[rc];
    B[qf];
    W[pn]
    LB[on:a]
    C[And White plays here before Black
can play the good move at A.]
    )
        (;
        B[pc]
        C[Blocking on the wide side is
normally correct, but doesn't
work well here.];
        W[qd];
        B[qe];
        W[re];
        B[qf];
        W[rf];
        B[qg];
        W[pb];
        B[ob];
        W[qb];
        B[nc];
        W[ie]
        C[After the joseki in the upper right
corner, this White play becomes
an ideal erasing move.]
        )
    )
)
