Shiva Purana
चैवोग्रतारिका प्रोक्ता महोग्रतारिकापि च॥ प्रादुर्भूता यतः सा वै मातंगीत्युच्यते भुवि॥ १५॥
She alone is said to be Ugratārikā and great Ugratārikā. She is called Mātaṅgī after the source from which she manifested herself.
english translation
caivogratArikA proktA mahogratArikApi ca॥ prAdurbhUtA yataH sA vai mAtaMgItyucyate bhuvi॥ 15॥
hk transliteration by Sanscript