Mahler book gives interesting account of Bruckner's publications

I recently read an interesting book on Gustav Mahler written by Alfred Mathis-Rosenzweig (1897-1948). His manuscript for this book, started in 1933 was thought to have been lost but was discovered at the Guildhall School in 1997 and translated into English in 2003. In the book, entitled "Gustav Mahler, New Insights into His Life and Work," the author devotes a large section to Mahler's relationship with Bruckner and his dedication to performing his teacher's music. Further, Mathis-Rosenzweig describes how Mahler pressured Emil Hertzka, the founder of Universal Edition, to buy up all the publication rights to Bruckner's symphonies since they were owned by several smaller publishing firms and recent mergers had made it next to impossible to get any of Bruckner's scores re-printed. Mahler even went so far as to contribute the royalties from his first four symphonies to cover the cost of the re-publication of Bruckner's symphonies which were becoming increasingly scarce. The author then delves into the National Socialist's campaign against Universal Edition and their condemnation of Bruckner's first published editions. Finally he levels intense criticism at Robert Haas citing that as the editor of the new Bruckner Edition, Haas should have prepared a detailed analysis of the preparation of Bruckner's scores for publication to help determine exactly what Bruckner had done and how the assistance by his associates and conductors were suggested and incorporated into the published editions. Instead, the author accuses Haas of becoming a public prosecutor of Bruckner's associates in his effort to discredit all of the first published editions. It is a fascinating analysis and a highly recommended book.