24. The liturgical books of the *forma extraordinaria* are to be used as they are. All those who wish to celebrate according to the *forma extraordinaria* of the Roman Rite must know the pertinent rubrics and are obliged to follow them correctly.
25. New saints and certain of the new prefaces can and ought to be inserted into the 1962 Missal[9], according to provisions which will be indicated subsequently.
26. As foreseen by article 6 of the Motu Proprio *Summorum Pontificum*, the readings of the Holy Mass of the Missal of 1962 can be proclaimed either solely in the Latin language, or in Latin followed by the vernacular or, in Low Masses, solely in the vernacular.
27. With regard to the disciplinary norms connected to celebration, the ecclesiastical discipline contained in the Code of Canon Law of 1983 applies.
28. Furthermore, by virtue of its character of special law, within its own area, the Motu Proprio *Summorum Pontificum* derogates from those provisions of law, connected with the sacred Rites, promulgated from 1962 onwards and incompatible with the rubrics of the liturgical books in effect in 1962.