| title | creator | language | description | tableOfContents | contributor | subject | created |
| The Egyptian Conception of Immortality | Reisner, George Andrew, 1867-1942 | en | | | | | 2004-05-01 |
| The Number Concept
Its Origin and Development | Conant, Levi Leonard | en | | | | | 2005-08-05 |
| The Machinery of the Universe
Mechanical Conceptions of Physical Phenomena | Dolbear, A. E. (Amos Emerson), 1837-1910 | en | | | | | 2009-07-18 |
| Essays on the Materialistic Conception of History | Labriola, Antonio, 1843-1904 | en | | | Kerr, Charles H. [Translator] | | 2010-06-01 |
| The Concept of Nature
The Tarner Lectures Delivered in Trinity College, November 1919 | Whitehead, Alfred North, 1861-1947 | en | | | | Nature; Science -- Philosophy; Knowledge, Theory of | 2006-07-16 |
| Conception Control and Its Effects on the Individual and the Nation | Barrett, Florence E. | en | | | | | 2004-10-31 |