The Blue Cliff Record (Bdk English Tripitaka, 75) by Yuan-Wu, Thomas Cleary (Translator), Chin Ko, J. C. Cleary (Translator) Translated from the Chinese by Thomas Cleary. This sutra consists of 100 koans selected by Ch'ung-hsien and is held in high regard by the Rinzai Zen Sect as a model text for instruction in the Zen practice. 

Secrets of the Blue Cliff Record : Zen Comments by Hakuin and Tenkei by Hakuin (Editor), Thomas Cleary (Translator), Denson (Editor) Thomas Cleary translated The Blue Cliff Record many years ago.In this new book Secrets of the Blue Cliff Record he makes available commentaries by Rizai master Hakuin and Soto master Tenkei. This book will be welcomed by those who have read,re-read and studied The Blue Cliff Record in detail. I recommend this books to students of The Blue Cliff Record everywhere!

The Zen Teachings of Instantaneous Awakening by Hui Hai - Zen Master Hui Hai, affectionately known as the Great Pearl, was of the same spiritual tradition as Hui Neng Ma Tsu and Huang Po. His style of teaching is very direct and just as pertinent today as it was 1200 years ago in China. John Blofeld, noted translator of the , taught Buddhism in Chinese temples before the Communist revolution. His love of China and knowledge of Buddhism enable him to translate this volume with feeling and insight. 

Sayings and Doings of Pai-Chang by Shih Huai-Hai

Review of above by Michael Harings: 

The Ch'an (Zen) Buddhist tradition can seem inscrutable to the Western mind. Pai-chang was a great Ch'an master in eighth-century China who channeled much energy into the culture surrounding Buddhism in his time. Reading through his sayings and speeches is a difficult though ultimately rewarding exercise. Though one might like to understand this Adept from an analytical or philosophical disposition, his teaching remains mind-transcending. For instance: 

One day as the master [Pai-chang] was walking along with Ma-tsu [his Teacher], they saw a flock of wild ducks fly by. 
The ancestor raid, "What is that?" 
The master said, "Wild ducks." 
Ma-tsu said, "Where have they gone?" 
The master said, "Flown away." 
Ma-tsu then turned around and grabbed the master's nose; feeling pain, the master let out a cry. 
The ancestor said, "Still you say, 'Flown away'?" 
At these words the master had insight.

Through stories like this one can begin to appreciate the sudden awakening through dramatic and startling means that is at the heart of Pai-chang's teaching and the Ch'an tradition. In addition to a brief collection of sayings, which are similar to the confrontive koan above, the largest portion of the book is devoted to the "Extensive Record". This record is a compilation of Pai-chang's talks, including questions and responses. It is the written "Record" of this Buddhist master's ego-interfering acts. 
In fact, what this tradition of Ch'an is pointing to in a rather enigmatic way is the incomparable Realization of the Buddha. Such Realization is beyond all language and description, and thus any attempt to describe it is futile. Another Buddhist Master, Seng-chao, spoke of this understanding as follows: "The way of enlightenment cannot be measured or calculated . . . Speaking of it is like setting up a target mound inviting an arrow." However, Pai-chang, like his mentors, gestures roward that Realization by explaining in a negative fashion everything that falls short of Enlightenment. This rhetoric can prove repetitious at times, but if one is receptive it can lead one to an intuitive taste of the ineffable. A typical example: 

If one says there is an enlightened nature, this is called slander by attachment, but to say there is no enlightened nature is called slander by falsehood. As it is said, to say that enlightened nature exists is slander by presumption, to say that it does not exist is slander by repudiation; to say that enlightened nature both exists and does not exist is slander by contradiction, and to say that enlightened nature is neither existent nor nonexistent is slander by meaningless argument.
This slap in the face of reason is given to awaken insight, to provoke the feeling of what exists beyond the ordinary presumptions individuals have about life and reality. Pai-chang's life and teaching work is worthy of persistent investigation. He powerfully affected the face of Chinese Buddhism in his time and through succeeding generations. This celebrated Master was able to turn the esoreric instructions of high Indian and Chinese Dharma into real practice for monastics, and to inculcate that wisdom itself into the wider culture.