Vinaya Pitaka
Breath mindfulness, in general, and this discourse's core instructions, in particular, can be found throughout the Pali Canon, including in the "Code of Ethics" (that is, in the "Vinaya Pitaka"'s "Parajika") as well as in each of the "Discourse Basket" ("Sutta Pitaka") collections ("nikaya"). From these other texts, clarifying metaphors, instructional elaborations and contextual information can be gleaned. These can also be found throughout the Chinese Agamas.