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The Tai Chi Classics & History of Tai Chi
The Taijiquan Classics by Barbara Davis

An excellent scholarly document that includes a history of taijiquan and
the classics, full English translations of the classics with commentary,
and the originals in Chinese.  Highly recommended.

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The Taijiquan Classics
Books on Tai Chi and Martial Arts History
Martial Musings: A Portrayal of Martial Arts in the 20th Century
by Robert W. Smith

Martial arts expert Robert Smith, a student of Cheng Man-Ching and other
great masters, provides an exceptional historical account of modern martial
arts.  A fascinating read.

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Martial Musings
Chinese Boxing: Masters and Methods
by Robert W. Smith

Robert Smith's in-depth descriptions of many modern masters of the
Chinese internal arts, including Cheng Man-Ching.

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Chinese Boxing
Tai Chi Ancestors: The Making of an Internal Art
by Douglas Wile

This historical work examines martial arts traditions of the 16th to 18th
century that contributed to the development of taijiquan and provides the
historical context of more than 2000 years of soft martial arts.

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Tai Chi Ancestors
The Essence of T'ai Chi Ch'uan: The Literary Tradition

Poetic translation of the Classics by Lo, Inn, Amacker, & Foe

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Essence of T'ai Chi Ch'uan
T'ai Chi Classics by Waysun Liao

Translations of the Classics along with background information on Tai
Chi and advanced essays on internal energy

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T'ai Chi Clasics
Lost Tai Chi Classics from the Late Ching Dynasty
by Douglas Wile

Translation and analysis of recently released 19th century
manuscripts on taijiquan history and practice.

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Lost Tai Chi Classics
The "Tai Chi Classics" are a revered assemblage of traditional
Chinese writings on taiji principles and the proper practice of taijiquan.