This name sits on a later shelf with no domain tag. Thrasybulus is a name attached to Athenian figures (son of Lycus, 403 BCE; another of Calydon). Neither is attested in the stored blurb as an author of ἐπιστολαί.
What this site holds is Fragments on Tyranny: two brief epistolary passages, including the anecdote of cutting the tallest stalks. Attribution is uncertain.
The Greek of those fragments is the holding. The heading is not a verified literary career.
Available Works
Fragments on Tyranny
Ἀπόσπασμα περὶ Τυραννίδος
2 passages
Also published as PDF.