Recommended Reading
Mindfulness with Breathing: A Manual for Serious Beginners
Ajahn Budhhadhasa Bhikkhu
Lays out the practice of anapasati meditation, literally mindfulness of the in and out breath.
"These are the roots of trees, O monks, these are empty huts. Meditate, monks, do not be negligent, or else you will regret it later. This is our instruction to you.”
~ The Buddha
AN 7:70
Lays out the practice of anapasati meditation, literally mindfulness of the in and out breath.