Volume 1:-
Volume One covers the Isa, Kena, Katha, and Taittiriya Upanishads....Volume Two covers the Aitareya, Mundaka, Mandukya, Karika and Prasna Upanishad. Each verse has the Devanagri Sanskrit, with English translation and commentary, with further commentary by Sankaracarya (Shankara). Also included is an Index to texts in Devanagri Sanskrit.
Volume 2:-
Volume two book presents a lucid exposition of select portions of this Upanishad in the light of modern thought and modern needs. The revered Swami has done this by freely drawing from contemporary scientific thought, biology, and physics, and by laying stress on the relevance of Vedantic ideas t these areas of modern thought.
The essence of the knowledge of the Vedas was called by the name of Vedanta,which comprises the Upanishads...strength is what the Upanishads speak to me from every page..therein lies strength enough to invigorate the whole world..they will call with trumpet voice upon the weak,the miserable,and the downtrodden of all races,all creeds,and all sects to stand on their feet and be free. Freedom,physical freedom,mental freedom,and spiritual freedom are the watch words of the Upanishads..the Upanishads are the Bible of India. Swami Vivekananda
Language: Sanskrit Shlokas along with English Commentary.