Josef Andreas Jungmann

Josef Andreas Jungmann (16 November 1889 – 26 January 1975) was a prominent Jesuit priest and liturgist. He was an influential advocate of the Liturgical Movement, and is known for his 2-volume history ''Mass of the Roman Rite'', which contributed to informing the reforms to the Mass during and following the Second Vatican Council, as well as his work in the post-Vatican II catechetical movement in the Catholic Church. Provided by Wikipedia