| Before 1920 | |
| 1920 | |
| 1930 | |
| 1940 | |
| 1950 | |
| 1960 | |
| 1970 | |
| 1980 | |
| 1990 | |
| The Future |
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Before 1920: Empirical Knowledge Base for Education |
Charles Darwin, 1809 - 1882
Darwin, Charles. (1871). The descent of man.
Available online:
- http://www.literature.org/Works/
Charles-Darwin/descent/ - http://www.infidels.org/library/historical/
charles_darwin/descent_of_man/
(includes a search engine)
Darwin, Charles. (1877). A biographical sketch of an infant. Mind, 7, 285-294.
Available online: