(;GM[1]FF[4]SZ[19]
GN[Good ko for White]
PC[http://senseis.xmp.net/?BQM271]AP[GoWiki:2009]
DT[2009-04-22]
C[Diagram from http://senseis.xmp.net/?BQM271

Good ko for White]
PL[W]

AB[pm][on][pn][qn][po][pp][qq][qr][rr][qs]
AW[oo][qo][op][qp][rp][sp][oq][pq][rq][sr][rs]
CR[rs]
LB[so:a]

;W[pr]C[W1]MN[1]
;B[ss]C[B2]MN[2]
;W[rn]C[W3]MN[3]
;B[rm]C[B4]MN[4]

;CR[rs]
LB[so:a]
)
