mechanics
| Author(s) | Title | Reference | |
|---|---|---|---|
| Reginald Lennard | Medieval Technology and Social Change, by Lynn White Jr. | 32/1, p. 45 | |
| J.D. North | Campanus of Novara and Medieval Planetary Theory: Theorica planetarum, by Francis S. Benjamin Jr., G. J. Toomer | 42/3, p. 272 |