latitude
1923 / Notes on the Knowledge of Latitudes and Longitudes in the Middle Ages / John Kirtland Wright / Isis 5 (1923) p. 75 [lien]
1977 / Planetary Latitudes, the Theorica Gerardi, and Regiomontanus / Claudia Kren / Isis 68 (1977) p. 194 [lien]