1. George Biddle Airy, , , Encyc. Brit., earlier editions, (also App. to the Greenwich Observations, 1854, ).
2. Special Pub.;Ross,1915
3. A new method of determining time;Willis;Astr. J.,1929
4. Instruments for observing equal-altitudes in astronomy;Chandon;Hydrographic Rev.,1935
5. New military surveying equipment;Little,1945