Shiva Purana
उत्तरस्यां दिशि तथा मुने सप्तर्ष यस्तथा ॥ यामा नाम तथा देवा आसन्स्वायंभुवेंतरे ॥ १० ॥
O sage, the seven sages are in the northern quarter. In the Svāyambhuva Manvantara there were the gods named Yāmas.
english translation
uttarasyAM dizi tathA mune saptarSa yastathA ॥ yAmA nAma tathA devA AsansvAyaMbhuveMtare ॥ 10 ॥
hk transliteration by Sanscript