Here are some resources for anyone interested in the historical aspects of the bodhisattva path in Sri Lanka and other Theravāda locations:
- Chandawimala Thero, Rangama. Bodhicitta in Theravāda Buddhism with Special Reference to the Abhayagiri Fraternity in Ancient Sri Lanka. Presentation for Third Korean Conference of Buddhist Studies, 2006.
Chandawimala Thero, Rangama. The Impact of the Abhayagiri Practices on the Development of Theravāda Buddhism in Sri Lanka. Doctoral Dissertation, 2007.
Chandawimala Thero, Rangama. Esoteric Buddhist Practice in Ancient Sri Lanka.
Holt, John Clifford. Buddha In The Crown: Avalokiteśvara in the Buddhist Traditions of Sri Lanka. Oxford University Press, 1991.
Sundberg, Jeffrey R. The Wilderness Monks of the Abhayagirivihāra and the Origins of Sino-Javanese Esoteric Buddhism. Bijdragen tot de Taal-, Land- en Volkenkunde, 2004.
And a few papers discussing the Pāḷi Yogāvacara texts:
- Crosby, Kate. History Versus Modern Myth: The Abhayagirivihāra, the Vimuttimagga and Yogāvacara Meditation. Journal of Indian Philosophy 27 (6), 1999.
Crosby, Kate. Studies in the Medieval Pāli Literature of Sri Lanka with Special Reference to the Esoteric Yogāvacara Tradition. Doctoral Dissertation, 2000.
Crosby, Kate. Tantric Theravāda: A Bibliographic Essay on the Writings of François Bizot and others on the Yogāvacara Tradition. Contemporary Buddhism, Vol. 1, No. 2, 2000.
All the best,