Long ago Westergaard, Rhys Davids and Ernst Kuhn,' had made the same suggestion, mainly on historical grounds, Mahinda, who took the texts to Ceylon, having been born at Vedisa in that district.
Oldenberg; and the more important parts of it have been translated into English by Rhys Davids and Oldenberg in their Vinaya Texts.
Of the seven treatises contained in the Abhidhamma Pitaka five, and one-third of the sixth, had by 1910 been published by the Pali Text Society; and one, the Dhamma Sangani, had been translated by Mrs Rhys Davids.
A description of the contents of all these books in the canon is given in Rhys Davids's American Lectures, PP. 44-86.