Gstr 9c fy 2018-19

For F.Y 2018-19 if your Turnover is more than 5 Crore than its mandatory to do GST audit and file Form GSTR 9C.
If your turnover more than 2 Crores but less than 5 Crore than only GSTR 9 Annual return is compulsory.

Any notification link u have pls share

As per Notification No. 16/2020 - Central Tax, dated 23rd March 2020, FORM GSTR-9C for FY 2018-19 has been made "MANDATORY" only for those persons whose Aggregate Turnover "Exceeds Rs. 5 crores." A new Proviso was inserted to Rule 80(3) of the CGST Rules 2017 specifically for the Financial Year 2018-19.