This game was later released as a revised version for 5500 yen on 1991-04-26. You will sometimes see that title as Isaki Shuugorou no Keiba Hisshou Gaku (Revised) or 井崎脩五郎の競馬必勝学 ニューパッケージ版.
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Isaki Shuugorou no Keiba Hisshou Gaku
Isaki Shuugorou no Keiba Hisshou Gaku