Ptolemy’s Doctrine of the Terms and Its Reception – Prof. Dr. Stephan Heilen – https://link.springer.com/chapter/10.1007/978-90-481-2788-7_3
Cosmos and Culture Nr. 11 – http://www.cultureandcosmos.org/issues/vol11.php
–https://www.skyscript.co.uk/terms.html – https://talk.vonabisw.de/Lehrgang/Terms.pdf
Forschung München – Dr. David Juste – https://ptolemaeus.badw.de/start – https://ptolemaeus.badw.de/work/27