Just when I thought all about Chen taiji have been written (at least the chinese books), I saw a few new books on the shelves when I visited the bookstores recently.  I usually try to buy them as they are relatively affordable compared to English books and their printing quality has improved a lot over the past few years.
One of the new book is by Ma Hong, titled 陈式太极拳劲道释秘-拆拳讲劲 . Roughly translated as Chen Style Taijiquan Secrets Explained – Dissecting the Routine to Explain the Jing.
I have not read it but …