Yoga Sutra 2.50 the fixating operations become long and fine
Sūtra II.50 The external, internal, and fixating operations, practised in terms of place, of time and of number, become long and fine Of these, stopping the flow after (a full) inhalation is the external; next, stopping the flow after (a full) exhalation is the internal. The third is the operation of fixation, not preceded by…