References – SN 54: Linked Discourses on Breath Meditation 
Readings by Ajahn Ñāṇiko: [Mindfulness of breathing]
Right Mindfulness pp. 93-96.
Vinaya: Book of the Discipline Part 1 p. 116-121, Pārājikā 3 origin story.
Sutta: AN 9.36: Jhāna.
Sutta: SN 54.8: Simile of the lamp.
The Four Foundations of Mindfulness [2015], Session 23
Teaching: Mindfulness of breathing is the practice that the Buddha recommended most. Contributed by Ajahn Pasanno. [Mindfulness of breathing] [Buddha/Biography]
Sutta: SN 54.11: The Buddha practices mindfulness of breathing while on retreat. [Meditation retreats]
Devotion and Ritual: Becoming the Buddha [2017], Session 3, Excerpt 11
Readings by Ajahn Pasanno:
Sutta: SN 54.12, Ānāpānasaṁyutta, “In Perplexity.”
Sutta: AN 4.61, “Worthy Deeds.”