The Threepenny Opera (Die Dreigroschenoper) is a “play with music” by Bertolt Brecht, adapted from a translation by Elisabeth Hauptmann of John Gay‘s 18th-century English ballad opera, The Beggar’s Opera, and four ballads by François Villon, with music by Kurt Weill. Although there is debate as to how much, if any, Hauptmann might have contributed to the text, Brecht is usually listed as sole author.

The work offers a socialist critique of the capitalist world. It opened on 31 August 1928 at Berlin’s Theater am Schiffbauerdamm.

Songs from The Threepenny Opera have been widely covered and become standards, most notably “Die Moritat von Mackie Messer” (“The Ballad of Mack the Knife“) and “Seeräuberjenny” (“Pirate Jenny“).

https://en.m.wikipedia.org/wiki/The_Threepenny_Opera

Symphony No. 2 by Gustav Mahler, known as the Resurrection Symphony, was written between 1888 and 1894, and first performed in 1895. This symphony was one of Mahler’s most popular and successful works during his lifetime. It was his first major work that established his lifelong view of the beauty of afterlife and resurrection. In this large work, the composer further developed the creativity of “sound of the distance” and creating a “world of its own”, aspects already seen in his First Symphony. The work has a duration of eighty to ninety minutes and is conventionally labelled as being in the key of C minor; the New Grove Dictionary of Music and Musicians labels the work’s tonality as C minor–E♭ major. It was voted the fifth-greatest symphony of all time in a survey of conductors carried out by the BBC Music Magazine.

https://en.wikipedia.org/wiki/Symphony_No._2_(Mahler)