Upietisti
Joachim Feller, Sonnet. In: Luctuosa desideria Quibus […] Martinum Bornium prosequebantur Quidam Patroni, Praeceptores atque Amici. Lipsiae [1689], pp. [2]–[3]. (Facsimile in: Reinhard Breymayer (Ed.): Luctuosa desideria. Tübingen 2008, pp. 24–25.) Here for the first time the newly detected source. – Less exactly cf. Martin Brecht: Geschichte des Pietismus, vol. I, p. 4.