Shiva Purana
उत्तमं मध्यमं नीचं त्रिविधं लिंगमीरितम् । मानतो मुनिशार्दूलास्तच्छृणुध्वं वदाम्यहम् २८ ।
Based on sizes the images are of three types—Excellent (Uttama), normal (Madhyama) and inferior (Nīca). O foremost of sages, I shall explain them, please listen.
english translation
uttamaM madhyamaM nIcaM trividhaM liMgamIritam । mAnato munizArdUlAstacchRNudhvaM vadAmyaham 28 ।
hk transliteration by Sanscript