(;GM[1]FF[4]SZ[19]
GN[white can not avoid ko]
PC[http://senseis.xmp.net/?GokyoShumyoSection3Problem75/Attempts]AP[GoWiki:2009]
DT[2009-04-22]
C[Diagram from http://senseis.xmp.net/?GokyoShumyoSection3Problem75/Attempts

white can not avoid ko]
PL[B]

AB[cb][hb][cc][ic][bd][ed][gd][hd][be][ce][de][fe]
AW[bb][bc][dc][ec][fc][gc][cd][dd]

;B[ab]C[B1]MN[1]
;W[db]C[W2]MN[2]
;B[ac]C[B3]MN[3]
;W[ca]C[W4]MN[4]
;B[ea]C[B5]MN[5]

;
)
