(;GM[1]FF[4]SZ[19]
GN[mistake by black]
PC[http://senseis.xmp.net/?GokyoShumyoSection3Problem50/Attempts]AP[GoWiki:2009]
DT[2009-04-22]
C[Diagram from http://senseis.xmp.net/?GokyoShumyoSection3Problem50/Attempts

mistake by black]
PL[W]

AB[db][fc][bd][dd][ed][ce][cf]
AW[cb][bc][cd]
LB[eb:a][be:b]

;W[dc]C[W1]MN[1]
;B[ec]C[B2]MN[2]
;W[cc]C[W3]MN[3]

;LB[eb:a][be:b]
)
