The Forster Codices - Three Small Notebooks Dating From the End of the Fifteenth to the Beginning of the Sixteenth Centuries
The Codex Hammer - Compiled about 1508-1510, a Synthesis of Leonardo’s Views on Nature
The Codex Trivulzianus - Leonardo's Attempt to Organise and Arrange that Part of the Italian Language Which Deals with Science, Philosophy, and Academic Subjects in General