Shiva Purana
यथाकथंचिद्विधिना रम्यं लिंगं प्रकारयेत् । पंचसूत्रविधानां च पार्थिवेन विचारयेत् २७ ।
By any means the phallic image shall be made beautiful. The Pañcasatra rite shall be performed with the earthen phallic image.
english translation
yathAkathaMcidvidhinA ramyaM liMgaM prakArayet । paMcasUtravidhAnAM ca pArthivena vicArayet 27 ।
hk transliteration by Sanscript