Prasthānatraya with Adi Śankaracharya Bhagavatpada's Bhashyam
(English Translations)
(Version Sep, 2022)
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Brahma Sutra (Nyaya Prasthāna)

Brahma Sutra Shankara Bhashya (Sanskrit only!)
Brahma Sutra Shankara Bhashya, V.M. Apte
Brahma Sutra Bhashya, Swami Gambhirananda
Brahma Sutra Bhashyam George Thibaut, Part 1
Brahma Sutra Bhashyam George Thibaut, Part 2

Principal Upanishads (Śruti Prasthāna)

Eight Upanishads Vol. 1 (Isa, Kena, Katha, and Taittirīya Upanishad), Swami Gambhirananda

Eight Upanishads Vol. 2 (Aitareya, Mundaka, Mandukya Karika and Prasna Upanishad), Swami Gambhirananda

Mandukya Upanishad & Karika with Shankara Bhashya, Swami Nikhilananda

Brihadaranyaka Upanishad with Shankara Bhashya, Swami Madhavananda

Chandogya Upanishad with Shankara Bhashya, Ganganath Jha

Aitareya &Taittiriya Upanishads with Shankara Bhashya
Bhagavad Gita (Smṛti Prasthāna)

Bhagavad Gita Bhashya (Sanskrit only)
Bhagavad Gita with the Commentary of Sri Shankaracharya, Alladi Mahadeva Sastri || (Mirror)

Bhagavad Gita with English Translation of Sri Sankaracharya's Sanskrit Commentary, Swami Gambhirananda
(without Upodghāta, Intro)

Srimad Bhagavad Gita Bhashya of Sri Sankaracarya
Upadeśasāhasri

Upadesasahasri, Swami Jagadananda
Other Works:

A Concordance of Adi Shankara (8 Volume-Set),
Br. Sutejas (Thomas Felber)
Vol. 1, Vol. 2, Vol. 3, Vol. 4, Vol. 5, Vol. 6, Vol. 7, Vol. 8

The Legacy of Adi Shankaracharya, Br. Sutejas (Thomas Felber) - (free edition without index).