مسائل المنتخبه (Articles Of Islamic Acts) - الخوئي، السيد أبوالقاسم - الصفحة ٢٥٨ - DOUBTS IN CONNECTION WITH PRAYERS

bowing of the following unit that he has not performed two prostrations he shouldperform them and if he recollects this during bowing or thereafter his prayers is void.
١١٨٦. If a person doubts whether or not he has performed an act, which is not a rukn and if he has become engaged in an act. which comes after it, he should ignorehis doubt. For example, if he doubts while reciting surah whether or not he has recited Surah al-Hamd he should ignore his doubt. And in case he recollects later that he hasnot performed that act, he should perform it if he has not become engaged with the next rukn. and if he has become engaged with the next rukn his prayers is in order. Hence,if, for example he recollects in qunut that he has not recited Surah al-Hamd he should recite it, and if he recollects it in bowing, his prayers is in order.
١١٨٧. If a person doubts whether or not he has said salaam of prayers, and he begins offering another prayers or ceases to be in the state of a person offeringprayers, owing to his having done something which nullifies prayers, he should ignore his doubt. And if he doubts before these things happen, he should say salaam even thoughhe may have engaged in Taqib.
II. Doubt After the Salaam (salutation)
١١٨٨. If a person becomes doubtful after the salaam of prayers as to whether or not he has offered the prayers correctly (e.g. if he doubts whether or not he hasperformed the bowing or doubts in connection with a ٤ unit prayers as to whether he has performed ٤ units or ٥ units) he should ignore his doubt. But if both sides of thedoubt lead to invalidity of the prayers (e.g. ii he doubts in connection with ٤ unit prayers as to whether he has performed ٣ units or ٥ units) his prayers would be void.

III. Doubt After the Time
١١٨٩. If a person doubts, after the time for prayers has already