(;GM[1]FF[4]SZ[19]
GN[Dropping back]
PC[http://senseis.xmp.net/?DroppingBackProblem1/Solution]AP[GoWiki:2009]
DT[2009-04-22]
C[Diagram from http://senseis.xmp.net/?DroppingBackProblem1/Solution

Dropping back]
PL[B]

AB[bb][cb][db][ac][cc][ad][bd][dg][eg][gg][eh][di][gi][bj][dj]
AW[eb][dc][ec][cd][gd][id][ae][be][ce][ee][df][ch][dh][ei][ej][ck][dk][ek]
CR[ae]

;B[cg]C[B1]MN[1]
;W[bh]C[W2]MN[2]
;B[bg]C[B3]MN[3]
;W[ag]C[W4]MN[4]

;CR[ae]
)
