Shiva Purana
स्वयं च कारणं कार्यं स्वस्य नैव कदाचन ॥ एकोव्यनेकतां यातोप्यनेकोप्येकतां व्रजेत् ॥ २८॥
He is not the creation of any one. Though single he assumes manifold shapes. Seeming to be many he becomes unified into one.
english translation
svayaM ca kAraNaM kAryaM svasya naiva kadAcana ॥ ekovyanekatAM yAtopyanekopyekatAM vrajet ॥ 28॥
hk transliteration by Sanscript