Commission Regulation (EC) No 937/2003 of 28 May 2003 amending Regulations (EC) No 668/2001, (EC) No 1500/2001, (EC) No 953/2002, (EC) No 968/2002, (EC) No 1081/2002 and (EC) No 2177/2002 opening standing invitations to tender for cereals held by certain intervention agencies.