Responsories for Holy Week Maundy Thursday and Good Friday respectively, rather than on a sequence of names referring to Maundy Thursday, Good Friday and Holy Saturday respectively. The responsories following each lesson of these matins (so also 27) were usually sung, and these are the Tenebrae Responsoria, or the Responsories for Holy Week. The name of a collection of such responsories may also refer to the Holy Triduum, as in Orlande de Lassus' "". Maundy Thursday is the fifth day of the Holy Week (Latin: Feria V or Feria Quinta). In Latin the feast is also indicated as "In Cœna Domini" ("At the meal
Determination of the day of the week that a year can start on, and leap years will alter the day of the week after February 29. This means that there are 14 configurations that a year can have. All the configurations can be referenced by a dominical letter, but as February 29 has no letter allocated to it a leap year has two dominical letters, one for January and February and the other (one step back in the alphabetical sequence) for March to December. For example, 2018 is a common year starting on Monday, meaning that 2018 corresponds to the 2007 calendar year and with the last