Manusmriti
तुलामानं प्रतीमानं सर्वं च स्यात् सुलक्षितम् । षट्सु षट्सु च मासेषु पुनरेव परीक्षयेत् ॥ ४०३ ॥
All weights and measures must be duly marked, and once in six months let him re-examine them.
english translation
tulAmAnaM pratImAnaM sarvaM ca syAt sulakSitam । SaTsu SaTsu ca mAseSu punareva parIkSayet ॥ 403 ॥
hk transliteration by Sanscript