Yazid bin 'Abdullah bin al-Shakhayr يزيد بن عبد الله بن الشخير · The Book of Purification

"When any one of you wakes from sleep to perform Wudu', then let him sniff water in his nose and blow it out three times, for the Shaitan spends the night on his nose."

"That is not menstruation, rather it is a vein. Tell her not to pray for the amount of time that her period used to last, then let her perform Ghusl and pray.' She used to perform Ghusl for every prayer.