مسائل المنتخبه (Articles Of Islamic Acts) - الخوئي، السيد أبوالقاسم - الصفحة ١٠٥ - KINDS OF HAIZ

١٠ days is all menses and the quantity of the first blood which comes earlier than the days of habit and that quantity of the second blood which comes after the days of habit is istihaza. For example, if the habit of a woman is to bleed from the ٣rd to the ١٠th of a month and in a particular month her blood comes from the Ist to the ٦th and then stops for two days and thereafter comes again up to the ١٥th the blood which comes from the ٣rd to the ١٠th is menses and that which comes on the Ist and ٢nd similarly from the ١١th to the ١٥th is istihaza.
(iv) That some quantity of the Ist and ٢nd blood comes during the days of her habit but the Ist blood which comes during the days of habit is for less than ٣ days. In that case it is not unlikely that the woman concerned may add the period during which her blood has come in the days of habit with a part of the period during which her blood has come before the days of her habit so as to make a total of ٣ days, and treat them as days of menses. In case, therefore, she treats that quantity of her ٢nd blood which has come duringdays of her habit to be menses and the period of that quantity and the quantity of the Ist blood which has been treated to be menses and the intervening period during whichblood has not come, when added together, do not exceed ١٠ days all these days are days of menses. Otherwise she should treat her Ist blood to be menses and the rest to be istihaza.
٤٩٠. If the blood of a woman who has the habit of time and number does not come at the time of her habit but comes on other days equal to the days of her habit withsigns of menses she should treat that very blood to be menses - whether it comes before the time of her habit or after it.
٤٩١. If the blood of a woman who has the habit of time and number comes at the time of her habit but the number of the days on which the blood comes is more or less than the days