K. W. Stevenson,Worship: Wonderful and Sacred Mystery (Washington, DC [1992]
H. Thurston, SJ, Lent and Holy Week (1904)
Dictionnaire d’ Archéologie Chrétienne et de Liturgie, ed. F.Cabrol, OSB, and H. Leclercq, (this appears to be in the public domain... in French. Would love to see it translated, but I'm not sure how much of a reasonable request as there are 15 volumes)