It's a snip at £6.61 on Amazon.
Buy it!
http://www.amazon.co.uk/dp/B00BEXREPQ/ref=tsm_1_fb_lk
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Tai Chi Internal Exercises for Ta Ji Quan Practioners
www.amazon.co.uk
So you've learnt your Tai Ji form and you want to get deeper into the mysterious 'Internal'. Inside this book you will find 31 different exercises to help you develop further using your own form as a vehicle for travel into the wilder reaches of T'ai Chi Chuan.