B.C. Law, in the article "Chronology of the Pali Canon", suggested the development of the Pali Tipitaka in stages as following:
(1) The simple statements of Buddhist doctrines now found, in identical words, in paragraphs or verses recurring in all the books.
(2) Episodes found, in identical works, in two or more of the existing books.
(3) The Silas, the Parayana group of sixteen poems without the prologue, the atthaka group of four or sixteen poems, the sikkhapadas.
(4) The Digha, Vol. l, the Majjhima, the Samyutta, the Anguttara, and earlier Patimokkha code of 152 rules.
(5) The Digha, Vols. II & III, the Thera-Theri-Gatha, the collection of 500 Jatakas, the Suttavibhanga, the Partisambhidamagga, the Puggala-pannatti and the Vibhanga.
(6) The Mahavagga and the Cullavagga, the Patimokkha code completing 227 rules, the Vimanavatthu and Petavatthu, the Dhammapada and the Kathavatthu.
(7) The Cullaniddesa, the Mahaniddesa, the Udana, the Itivuttaka, the Suttanipata, the Dhatukatha, the Yamaka and the Patthana.
(8) The Buddhavamsa, the Cariyapitaka and the Apadana.
(9) The Parivarapatha.
(10) The Khuddakapatha.