Prasthanatrayi

Prasthanatrayi (Sanskrit: प्रस्थानत्रयी, IAST: Prasthānatrayī), literally, three sources (or axioms), refers to the three canonical texts of theology having epistemic authority, especially of the Vedanta schools. It consists of:[1]

The Upanishads, known as Upadeśa Prasthāna (injunctive texts), and the Śruti Prasthāna (the starting point or axiom of revelation), especially the Principal Upanishads.
The Bhagavad Gita, known as Sādhana Prasthāna (practical text), and the Smṛti Prasthāna (the starting point or axiom of remembered tradition)
The Brahma Sutras, known as Sūtra Prasthāna (formulative texts) or Nyāya Prasthāna or Yukti Prasthāna (logical text or axiom of logic)

Sometimes,
Brahma / Paramatma
Jeevatma and
Jagat
are also referred to as Prasthanatrayi