Brihat Samhita
षडनागतानि पौष्णाद्द्वादश रौद्राच्च मध्ययोगीनि । ज्येष्ठऽद्यानि नवऋक्षाण्युडुपतिनाअतीत्य युज्यन्ते ॥ ४-०७ ॥
In the six lunar mansions beginning from Revatī (the 27th) the stars are towards the east; and in the twelve beginning from Ārdrā (the 6th) they are in the centre; and in the nine beginning from Jyeṣṭhā (the 18th) they are in the west of the several mansions; and the moon’s conjunction with the several lunar mansions is said to take place when the moon is in the middle of these mansions.
english translation
SaDanAgatAni pauSNAddvAdaza raudrAcca madhyayogIni । jyeSTha'dyAni navaRkSANyuDupatinAatItya yujyante ॥ 4-07 ॥
hk transliteration by Sanscript