Ernst Heckel. The worlds mysteries. In Russian /Ernst Gekkel. Mirovye zagadki. Public Studies on Monistic Philosophy. With a Foreword: Creed Creeds of Pure Reason. Moscow. Ivanovs book, 1907, 424s. We have thousands of titles and often several copies of each title may be available. Please feel free to contact us for a detailed description of the copies available. SKUalb6c9dbdbdcf550efb.