Vedantasara - Verse 199
Sanskrit
ततश्चास्य सुषुप्तेश्चाभेदशङ्का न भवति । उभयत्र वृत्त्यभाने समानेऽपि तत्सद्भावासद्भावमात्रेणानयोर्भेदोपपत्तेः
Swami Nikhilananda's Translation
Therefore there is no apprehension of its being identical with the state of deep sleep. For, though the mental state appears in neither, yet the difference between them lies in this that it exists in the Nirvikalpa Samadhi, but in deep sleep it does not.
Index: Vedantasara

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