"Theravada (pronounced — more or less — "terra-VAH-dah"), the "Doctrine of the Elders," is the school of Buddhism that draws its scriptural inspiration from the Tipitaka, or Pali canon, which scholars generally agree contains the earliest surviving record of the Buddha’s teachings."
The Buddha’s Teachings As It is by Ven. Bhikkhu Bodhi
Mindfulness in Plain English [free ebook] by Ven. Gunaratana
In The Buddha’s Words by Ven. Bhikkhu Bodhi
The Four Foundations of Mindfulness in Plain English by Ven. Gunaratana
Practicing the Jhanas by Stephen Snyder and Tina Rasmussen
Satipatthana: The Direct Path to Realization by Ven. Analayo