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In page Shatranj:

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The works of al-Adli and as-Suli contain collections of tabiyat. Tabiyat were usually given as position on a half-board with some comments about them. The concrete sequence of moves to reach them was not specified. In his book Al-Lajlaj analyzed some tabiya in detail. He started his analysis from some given opening, for example "Double Mujannah" or "Mujannah–Mashaikhi", and then continued up to move 40, giving numerous variations.[citation needed]