Shiva Purana
देशिकेनाप्यनुज्ञातः प्राङ्मुखो वाप्युदङ्मुखः ॥ दर्भासनो दर्भपाणिः प्राणापानौ नियम्य च ॥ ८० ॥
With the permission of the śāstra one should face east or north He sat on a straw seat and held a straw in his hand and controlled his breathing and expiration.
english translation
dezikenApyanujJAtaH prAGmukho vApyudaGmukhaH ॥ darbhAsano darbhapANiH prANApAnau niyamya ca ॥ 80 ॥
hk transliteration by Sanscript