commiss decis ecsc march temporari postpon date payment steel product levi commiss european commun regard treati establish european coal steel commun articl thereof consult council articl decis levi paid twenti dai month respect product preced month exception mark fall price deterior condit sale steel market led fall receipt undertak temporari cash flow difficulti adopt decis sole articl derog articl decis high author ecsc levi due steel product month march decemb payabl twenti dai month month product levi due product month novemb decemb payabl date product month januari februari februari march decis bind entireti directli applic member state brussel march commiss presid françoi xavier ortoli oj