During the Easter Time, the Gregorian chants of the Ordinary of the Mass are generally taken form the Mass I, also called Lux et Origo. Kyrie (in forma ordinaria) Kyrie (in forma extraordinaria) Gloria Sanctus Agnus Dei

A brief video with highlights of the ordinations of May 2012, 5th  in Rome of 35 priests by the Prelate of Opus Dei.