| Author: | Haeckel, Ernst, 1834-1919 |
| Subject: | B, Religion and science, Evolution, Monism |
| Format: | Electronic text |
| Date issued: | 2019 |
| Language: | German |
| Publisher: | Project Gutenberg, |
| Rights: | Public domain in the USA. |
| Download link: | Die Welträtsel : Gemeinverständliche Studien über Monistische Philosophie [electronic resource] / Ernst Haeckel |