Mukhtasar Muslim

Sayyiduna Abu Hurairah (may Allah be pleased with him) reports that the Messenger of Allah (peace and blessings be upon him) said: Do not fast one or two days before Ramadan, except for a person who used to fast on a particular (fixed) day, and that day coincides (with these days), then he may fast on his fixed day. (For example, if he used to fast on Thursday and Friday, and the 29th or 30th of Sha’ban falls on those days, then he may fast.)