Erhardt, Rudolf von. |
Archimedes' Sand-reckoner : Aristarchos and Copernicus / by Rudolf von Erhardt and Erika von Erhardt-Siebold |
In: Isis Vol. 33 (1942), p. 578-602 |
Erhardt-Siebold, Erika von, n. 1890 |
The heliotrope tradition / Erika von Erhardt-Siebold |
In: Osiris Vol. 3 (1937), p. 22-46 |
Erhardt, Rudolf von. |
The helix in Plato's astronomy / by Rudolf von Erhardt and Erika von Erhardt-Siebold |
In: Isis Vol. 34 (1942), p. 108-110 |
Sarton, George, 1884-1956 |
Remarks on the theory of temperaments / by George Sarton ; with a temperament text of c. 1480 edited by Erika von Erhardt-Siebold |
In: Isis Vol. 34 (1943), p. 205-208 |