Before revision: Among the great figures of Christian heortology, we can cite the Sulpician Pierre Batiffol and his History of the Roman Breviary published in 1893, Hartmann Grisar and his Analecta Romana published in 1899, or even the academician canon Louis Duchesne and his monumental studies on the Origins of Christian worship.
After revision: Prominent heortologists were the Sulpician Pierre Batiffol who published History of the Roman Breviary published in 1893, Hartmann Grisar who published Analecta Romana in 1899, and the canon Louis Duchesne who publishd studies on the Origins of Christian worship.