Steinle, F. Categorization and Experiment: Charles Dufay and the Two Electricities / Friedrich Steinle. Spaces of classification.(2003).
Chicago-viite (17. p.)Steinle, Friedrich. "Categorization and Experiment: Charles Dufay and the Two Electricities / Friedrich Steinle." Spaces of Classification.(2003) .
MLA-viite (8. p.)Steinle, Friedrich. "Categorization and Experiment: Charles Dufay and the Two Electricities / Friedrich Steinle." Spaces of Classification.(2003), .
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.