Shiva Purana

siva.sh/siva-purana/uma-samhita/27/28

तुरीया देवि भूतानां योगिनां ध्यानिनां तथा ।। सुखासने यथास्थानं योगी नियतमानसः ।। २८।।

sanskrit

The fourth, O Devi, is the fourth of all beings, the yogis and the meditators. The yogi should sit in a comfortable seat with a fixed mind.

english translation

turIyA devi bhUtAnAM yoginAM dhyAninAM tathA || sukhAsane yathAsthAnaM yogI niyatamAnasaH || 28||

hk transliteration by Sanscript