1. Accuracy of marine navigation;Weems;Navigation, Los Angeles,1951
2. Accuracy of marine navigation;Weems;Navigation, Los Angeles,1951
3. Some observations of refraction at low altitudes and of astronomical position-line accuracy;Peterson;Journal,1952
4. Investigations into the dip of the horizon;Freiesleben;Journal,1950
5. The accuracy of observations made with marine sextants;Smiley;Navigation, Los Angeles,1951