Students often ask me if there has a been a particular book or books that I referred to when reading the taijiquan classics.
Over the years I have kept two books close at hand;
(i) Essence of Tai Chi Chuan: The Literary Tradition
by Benjamin Pang Jeng Lo, Martin Inn (Editor), Robert Amacker (Editor)
(ii) True to the Art - Wee Kee Jin's book Taijiquan
I have found Wee Kee Jin's book to be one of the best books to read about Taijiquan Classics, particularly his interpretation of the classics in his discussion sections.
The book is no longer in print but to purchase a copy click link in brackets below and it will take you to his website.
(link to Wee Kee Jin website book store).