Chen Taijiquan
I recommend the following book to supplement your Chen Style Taijiquan training.
Chen Style: The Source of TaijiquanThe Way of Energy:  Mastering the Chinese Art of Internal Strength with Chi Kung Exercise (A Gaia Original)Xing Yi Nei Gong: Xing Yi Health Maintenance and Internal Strength Development
Chen Style: The Source of Taijiquan
by Davidine Sim

General coverage of Chen Style Taijiquan. This was my first taiji book.
The Way of Energy: Mastering the Chinese A...
by Master Lam Kam-Chuen
$10.85
Standing is an important foundation to taijiquan.
Xing Yi Nei Gong: Xing Yi Health Maintenanc...
by Dan Miller

This book offers some very clear descriptions on how to hold your body.
Taijiquan: The Art Of Nurturing, The Science Of PowerThe Taijiquan Classics: An Annotated TranslationThe Dao of Taijiquan: Way to Rejuvenation (Tai Chi)
Taijiquan: The Art Of Nurturing, The Scienc...
by Yang Yang

This is a fantastic book that combines taiji theory with science.
The Taijiquan Classics: An Annotated Transl...
by Barbara Davis
$12.71
Translations of the five core texts of Taijiquan.
The Dao of Taijiquan: Way to Rejuvenation (...
by Jou Tsung Hwa
$13.57
Discussion of the history and evolution of taijiquan, including Chen, Yang and Wu Styles, philosophy, foundation and more.
Nei Jia Quan, 2nd edition: Internal Martial ArtsThe Power of Internal Martial Arts and Chi: Combat and Energy Secrets of Ba Gua, Tai Chi and Hsing-IOld Frame Chen Family Taijiquan
Nei Jia Quan, 2nd edition: Internal Martial...
by Jess O'Brien
$14.93
Interviews with high level practitioners of the Chinese internal martial arts, Xing Yi, Taiji and Bagua.
The Power of Internal Martial Arts and Chi:...
by Bruce Frantzis
$18.45
Old Frame Chen Family Taijiquan
by Mark Chen
$13.57