Also highly recommended:
Mahāyāna Buddhism: the doctrinal foundations by Paul Williams
The Awakening of Faith: attributed to Aśvaghoṣha by Yoshito S. Hakeda
The Surangama Sutra: A New Translation by Hsüan Hua OR Surangama Sutra by Lu-Kuan-Yu
Cultivating Original Enlightenment: Wonhyo's Exposition of the Vajrasamādhi-sūtra by Robert E. Buswell
The Sutra of Perfect Enlightenment: Korean Buddhism's Guide to Meditation (with commentary by the Sŏn Monk Kihwa) by A. Charles Muller
Zongmi on Chan by Jeffrey L. Broughton
Tracing Back the Radiance: Chinul's Korean way of Zen by Robert E. Buswell
"If the Buddha-Nature is seen, there will be no seeing of a nature in any thing."
(Nirvana Sutra, T12n374p521b3; tr Yamamoto)
"Neither cultivation nor seated meditation — this is the pure Chan of Tathagata."
(Mazu Daoyi, X1321p3b23; tr. Jinhua Jia)
“Don’t rashly seek the true Buddha;
True Buddha can’t be found.
Does marvelous nature and spirit
Need tempering or refinement?
Mind is this mind carefree;
This face, the face at birth."
(Nanyue Mingzan: Enjoying the Way, tr. Jeff Shore; T2076p461b24-26)