Contemporary Sources.. Starting at this page you can reach several sources on Lortzing.  "Nun kommt der Freiheit grosser Morgen", an article about Lortzing's "Regina", written by Jürgen Lodemann.  Indispensable for a good comprehesion of Lortzing's view on the aesthetics of opera is his interview with  Johann Christian Lobe (1797 -1881), published in "Consonanzen und Dissonanzen", Leipzig 1869. There is also a pdf-file. All articles on Lortzing as published in the "Allgemeine Musikalische Zeitung" are available on this website.