definiens: means the auditors ( from time to time ) of the Com pany or, if they are unwilling or unable to act, an independent firm of chartered acc ountants ( of international repute ) as the parties s hall agree ( or, if they are unable to reach agreement wi thin [ * * * ] of a notice to agree being served by eit her party on the other, as determined by the [ * * * ] on t he [ * * * ] ) ; 1.17 means each successive period of three ( 3 ) calenda r months commencing on 1 January, 1 April, 1 July and 1 October, except th at the first Calendar Quarter of the Term shall commence on the Effective Date and end on the day i mmediately prior to the first to occur of 1 January, 1 April, 1 July or 1 October after the Effective Da te and the last Calendar Quarter shall end on the l ast day of the Term