Abrogation and its varieties in the verses of Quran

Abrogation of Quranic verses has been of those problems always dealt with in the fields of jurisprudence, hadith and commentary by Muslim commentators and scholars. On the question what of abrogation there can be found four schools: removal, repelling, address and explanation among which the first seems to be in more harmony with Quran. For the abrogator, abrogation is in four forms: Quran by Quran, Quran by Sunnah, Sunnah by Quran and Sunnah by Sunnah. The traditions referring to verses by verses abrogation can be regarded as the cases of Quran by Quran abrogation. Shiite, contrary to Sunnite who agrees with three kinds of abrogation including judgment, recital and judgment and recital, only has agreed with the first. In this way, the traditions apparently referring to abrogation of recital, should not be necessarily considered of such reference.