 According to scholars such as Rupert Gethin and Peter Harvey, the oldest recorded teachings are contained in the first four Nikayas of the Sutta Pitaka and their various parallels in other languages, together with the main body of monastic rules, which survive in the various versions of the patimokkha.Scholars have also claimed that there is a core within this core, referring to some poems and phrases which seem to be the oldest parts of the Sutta Pitaka.The reliability of these sources, and the possibility to draw out a core of oldest teachings, is a matter of dispute.