(;
AB[pr][or][qq][pq][rp][qn]
AW[nr][oq][mq][op][ro][qo][po][rn]
PL[W]
C[Status?

Source:
    "Life and Death", Davies  ch 31, 3]
(;
B[rr]
C[Black clearly lives.  This move is best.]
)
    (;
    W[rr]
    C[White's obvious and best move.]
    (;
    B[rq]
    C[Black can fall back here to try to create some eye-shape, but ...];
    W[sp]
    C[... White only has to hane here to kill Black, which the reader can easily verify.]
    )
        (;
        B[sp]
        C[Toughest defense.]
        (;
        W[qp]
        C[Forcing from the outside looks obvious, but fails!];
        B[rq];W[sr]
        C[White seems to have created a dead shape, but Black's eye-space is just big enough!]
        (;
        B[rs]
        C[Correct];
        W[qs];B[qr];W[ss];B[os]
        C[Black lives in seki.]
        )
            (;
            B[os]
            C[Inferior.];
            W[rs];B[qs];W[qr];B[sq]
            C[White has an unfavorable 3 step ko.]
            )
        )
            (;
            W[rq]
            C[Pushing from the inside is correct!];
            B[qp];W[os];B[rs];W[sr];B[ps];W[qr]
            C[Black dies.]
            )
        )
    )
)

