As many might have realised, the digitised collection of medieval music treatises has not been anymore available for months.
They promised to restore TML at its last address:
Recently, the "Jacobs School of Music" published this notice:
https://www.chmtl.indiana.edu/hmt/thesauri/index.html
Meanwhile in urgent cases you can use the collection over a screened portal, but the search function does not work easily.
The best way to use it, is to go to the screened TML:
https://lightseagreen-dog-349934.hostingersite.com/tml/router.php/index.html
For search you click at the first menu item "? Menu" for expanded search where you click a second time either on "search" or "browse" (you will anyway end up browsing, so it does not really matter). You can check the boxes to limit the results by century. This way, you might find faster the edition you are looking for.
Unfortunately, a search under the name of the editor does currently not work and you might need some time, but it is there!
Replies
FENYX : ALTER THESAURUS SCRIPTORUM MUSICORUM
Another alternative which works fine:
https://fenyx.me/browse/9th-11th