(;GM[1]FF[4]SZ[19]
GN[corner]
PC[http://senseis.xmp.net/?GokyoShumyoSection3Problem51/Attempts]AP[GoWiki:2009]
DT[2009-04-22]
C[Diagram from http://senseis.xmp.net/?GokyoShumyoSection3Problem51/Attempts

corner]
PL[B]

AB[ib][bc][cc][ic][ad][bd][be][ce][ee][ge][he][ef]
AW[bb][cb][hb][ac][dc][gc][cd][dd][gd]

;B[fb]C[B1]MN[1]
;W[fc]C[W2]MN[2]
;B[gb]C[B3]MN[3]

;
)
