There are few resources dedicated to the “yoga of nonapprehension” (Skt. anupalambhayoga; Ch. yǐwúsuǒdégù 以無所得故), that is to say the nonapprehension of sensory experience, which is the principal meditation approach referenced in the (Chinese) Heart Sutra.
PRIMARY SOURCES
Cūḷasuññatā Sutta (MN 121) [This sutta has a brief outline of the practice of inattention to sensory experience leading to cessation and emptiness.] Sujato’s translation on Cutta Central.
Xiǎo kōng jīng 小空經 (MĀ 190) https://suttacentral.net/ma190/lzh/taisho?reference=none&highlight=false [translated in Anālayo 2015]
མདོ་ཆེན་པོ་སྟོང་པ་ཉིད་ཅེས་བྱ་བ། Śūnyatā-nāma-mahāsūtra. [Translated in Skilling 1994]
SECONDARY SOURCES
Anālayo. (2015). Compassion and Emptiness in Early Buddhist Meditation. Windhorse Publications. [Includes a translation of Xiǎo kōng jīng 小空經 (MĀ 190). And instruction on how to approach non-attention to sensory experience]
Anālayo. (2021) “Being Mindful of What is Absent.” Mindfulness 13: 1671-1678.
Satyadhana. (2014). “The Shorter Discourse on Emptiness (Cūḷasuññatasutta, Majjhima-nikāya 121): translation and
commentary.” Western Buddhist Review 2014 (6): 78–104. https://thebuddhistcentre.com/system/files/groups/files/satyadhana-formless_spheres.pdf
Skilling, Peter (1994). Mahāsūtras: Great Discourses of the Buddha. Vol. I: Texts. Oxford: Pali Text Society.
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