(;GM[1]FF[4]SZ[19]
GN[Variation]
PC[http://senseis.xmp.net/?RTGProblem12/Solution]AP[GoWiki:2009]
DT[2009-04-22]
C[Diagram from http://senseis.xmp.net/?RTGProblem12/Solution

Variation]
PL[B]

AB[ab][cb][eb][ac][cc]
AW[fb][hb][ec][fc][ad][bd][cd][dd]

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

;
)
