Robert Hume, Mandukya Upanishad, Thirteen Principal Upanishads, Oxford University Press, page 370-371
Max Muller, The Upanishads, Part 2, Mandukya Upanishad, Oxford University Press, page 34-35
Robert Hume, Mundaka Upanishad, Thirteen Principal Upanishads, Oxford University Press, pages 372-373
Mundaka Upanishad, in Upanishads and Sri Sankara's commentary - Volume 1: The Isa Kena and Mundaka, SS Sastri (Translator), University of Toronto Archives, pages 138-152
Hume translates this as "imperishable Brahma", Max Muller translates it as "indestructible Brahman"; see: Max Muller, The Upanishads, Part 2, Mundaka Upanishad, Oxford University Press, page 36
The Sanskrit word used is Vyadh, which means both "penetrate" and "know"; Robert Hume uses penetrate, but mentions the second meaning; see: Robert Hume, Mundaka Upanishad, Thirteen Principal Upanishads, Oxford University Press, page 372 with footnote 1
