 The Swedish Mass draws from a number of different sources, though Luther’s "Formulae Missae" is apparent in regards to the Eucharistic structure This included revising the calendar along similar lines as those in Germany.Laurentius Petri further revised the Swedish Mass 1557.In large part, the Swedish liturgy retained “vestments, altars and frontals, gold and silver chalices and patens” and many other “popish” customs.