Commission Regulation (EC) No 1083/2000 of 23 May 2000 amending Regulations (EC) No 1667/98, (EC) No 1735/98, (EC) No 1758/98, (EC) No 1759/98, (EC) No 1760/98, (EC) No 2198/98, (EC) No 1392/1999 and (EC) No 441/2000 opening standing invitations to tender in the market of cereals held by certain intervention agencies