(;GM[1]FF[4]SZ[19]
GN[Solution]
PC[http://senseis.xmp.net/?GokyoShumyoSection5Problem7/Solution]AP[GoWiki:2009]
DT[2009-04-22]
C[Diagram from http://senseis.xmp.net/?GokyoShumyoSection5Problem7/Solution

Solution]
PL[B]

AB[bb][db][gb][dc][ec][fc][gc][ad][bd][cd][de]
AW[da][ga][ab][cb][eb][fb][hb][bc][hc][hd][be][fe][cf][df][ef]

;B[ba]C[B1]MN[1]
;W[ca]C[W2]MN[2]
;B[cc]C[B3]MN[3]
;W[aa]C[W4]MN[4]

;
)
