Essentials of the Upanishads
This is a detailed essay on the Upanishads, one of the types of source texts of Vedanta, giving relevant quotes and background information.
www.dvaita.org/shaastra/upanishad.html   reviews

Ish v sya Upanishad
A Foreword, Preface, and Translation of this ancient text of Vedanta.
www.dvaita.org/sources/shruti/translation.html   reviews