85. In the Order of Readings for ritual Masses the references given are to the texts already published for the individual rites. This obviously does not include the texts belonging to celebrations that must not be integrated with Mass. 
One such celebration would be the sacrament of penance.
86. The Order of Readings for Masses for various needs and occasions, votive Masses, and Masses for the dead provides many texts that can be of assistance in adapting such celebrations to the situation, circumstances, and concerns of the particular groups taking part. 
And these Masses indeed have the most variety in the Lectionary.
87. In ritual Masses, Masses for various needs and occasions, votive Masses, and Masses for the dead, since many texts are given for the same reading, the choice of readings follows the criteria already indicated for the choice of readings from the Common of Saints.
88. On a day when some ritual Mass is not permitted and when the norms in the individual rite allow the choice of one reading from those provided for ritual Masses, the general spiritual welfare of the participants must be considered. 
Funerals come to mind. Weddings also. A reminder: in such cases some sacraments may still be celebrated on the days in question; it’s just that the prayers and readings must be chosen from the Mass of the day.