Não informado. (1920). Discovery: The magazine of scientific progress. Professional and Industrial Publishing.
Παραπομπή σε μορφή Chicago (17η εκδ.)Não informado. Discovery: The Magazine of Scientific Progress. London: Professional and Industrial Publishing, 1920.
Παραπομπή σε μορφή MLA (8th εκδ.)Não informado. Discovery: The Magazine of Scientific Progress. Professional and Industrial Publishing, 1920.
Πρόσοχή: Οι παραπομπές μπορεί να μην είναι 100% ακριβείς.