2017 July 8, Matthieu Ricard, Enlightened Vagabond: The Life and Teachings of Patrul Rinpoche, Shambhala Publications, →ISBN, page 159:
When Önpo Tenga arrived, he said that no one else should be sent for until Patrul's post mortem meditation, or thukdam, was completed.
2018 June 11, Dalai Lama, The Life of My Teacher: A Biography of Kyabjé Ling Rinpoché, Wisdom Publications, →ISBN, page 2:
When Ling Rinpoché passed away on December 25, 1983, he remained seated cross-legged in thukdam for thirteen days—a state in which all vital signs have ceased yet the body remains without decomposition.
2021 August 3, Sarah Shaw, Kate Crosby, Roger R. Jackson, Gil Fronsdal, Secularizing Buddhism: New Perspectives on a Dynamic Tradition, Shambhala Publications, →ISBN, page 251:
Buddhists believe, there remains the possibility that there are extraordinary mental states that do not depend on the neurological system—namely, the meditative experiences of advanced tantric yogis, especially those who have entered the postmortem concentration on the clear-light nature of the mind known as thukdam.
