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ECO A91

ECO A00–A99 — Flank openings: 1.c4, 1.Nf3, 1.f4 and other first moves, plus early Indian and Benoni systems.

1 named opening lines are classified under ECO code A91.

Dutch Defense: Classical Variation, Blackburne Attack — 1.d4 f5 2.c4 Nf6 3.g3 e6 4.Bg2 Be7 5.Nh3