Zygmunt Mycielski wrote diaries throughout his life, but it was only after the war that he wrote them thinking that they might be published one day. He gave some fragments to friends to read, depositing the various notebooks with people he trusted, afraid that the communist government might confiscate them. They were published in four volumes after the composer’s death. Critics believe that Zygmunt Mycielski’s diaries are among the most important diary documents of the twentieth century. 

Niby-dziennik [Quasi-Diary] was prepared for publication by Mycielski himself, although the composer forbade it to be published before 1995. The volume covers the period from 2 November 1969 to 14 January 1981.