Commission Regulation (EC) No 19/98 of 7 January 1998 suspending the sale of butter from public stocks pursuant to Regulation (EEC) No 3143/85 on the sale at reduced prices of intervention butter intended for direct consumption in the form of concentrated butter and the granting of aid pursuant to Regulation (EEC) No 429/90 on the granting by invitation to tender of an aid for concentrated butter intended for direct consumption in the Community