What are the recommended and sufficient wording requirements for the oath in Qasama (oath taking in case of unknown homicide)?

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It is recommended to use emphatic wording in the oath of Qasama, such as stating: 'By Allah, other than Whom there is no god, the Knower of the stealthy glances and what the breasts conceal.' However, brevity suffices if one limits the oath to the word 'Wallah' (By Allah), or uses 'Wallahi', 'Billahi', or 'Tallahi', observing the required Arabic case endings (accusative/genitive for the preposition). If the oath is pronounced with a damma (nominative) or fatha (accusative) on the preposition, it constitutes a grammatical error (lahn). The Qadi states that this grammatical error is excusable whether intentional or accidental because it does not alter the meaning, a view held by Al-Shafi'i.