Visuddhimagga - The Path of Purification - The Classic Manual of Buddhist Doctrine and Meditation by Buddhaghosa
One of Buddhism's foundational texts, a systematic examination and condensation of Buddhist doctrine and meditation technique.
Seven Works of Vasubandhu - the Buddhist Psychological Doctor - by Stefan Anacker
The seven treatises presented here are complete works with a most varied range of topics and serve at least as an introduction to his thought.
A Comprehensive Manual of Abhidhamma - The Abhidhammattha Sangaha of Acariya Anuruddha — by Bhikkhu Bodhi
This is the classical introduction to the study of Abhidhamma - the Buddhist philosophy of mind and mental processes.
Gateway to Knowledge - The Gate for Entering the Way of a Pandita — by Jamgon Mipham
A condensation of the Buddhist Canon and its accompanying commentaries. Consolidating the intent of Buddha Shakyamuni's teachings into a unified body of text books, it is the philosophical backbone of the living tradition of Tibetan Buddhism.
Indo-Tibetan Classical Learning and Buddhist Phenomenology — by Jamgon Kongtrul - The Treasury of Knowledge - Volume 4
Concisely summarizing the theoretical fields of knowledge to be studied prior to the cultivation of reflection and discriminative awareness.
Myriad Worlds — by Jamgon Kongtrul - The Treasury of Knowledge - Volume 1
Describes four major cosmological systems found in the Tibetan tradition - those associated with the Hinayana, Mahayana, Kalachakra and Dzogchen teachings - each more subtle and profound than the last.