https://penelope.uchicago.edu/Thayer/E/Roman/Texts/Diodorus_Siculus/home.html
LacusCurtius • Diodorus Siculus
The Library of History, in English translation: Books 1‑32 are complete. Part of a very large site on classical Antiquity.
lacuscurtius
https://penelope.uchicago.edu/Thayer/E/Roman/Texts/Plutarch/home.html
Plutarch on LacusCurtius
Entry page to the works of Plutarch on this site: all the Lives and Comparisons, and 1900+ printed pages (about 45%) of the Moralia.
plutarchlacuscurtius