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

Seo-Cho]
PL[W]

AB[pd][po][jp][fq][pq]
AW[dd][qj][cn][dp]
LB[qf:a]

;W[nc]C[W1]MN[1]
;B[pg]C[B2]MN[2]
;W[qm]C[W3]MN[3]
;B[kd]C[B4]MN[4]

;LB[qf:a]
)
