KeYmaera X Tutorial
An ultra short synopsis of what you'll need to keep handy about the KeYmaera X Prover for Hybrid Systems is on the KeYmaera X Cheat Sheet.
A great practical way to learn how to use the KeYmaera X Prover for Hybrid Systems is via the KeYmaera X Tutorial:
Video: User Tutorial Video for KeYmaera X
The most comprehensive and readable background on the differential dynamic logic that the KeYmaera X Prover for Hybrid Systems provides can be found in the Textbook: Logical Foundations of Cyber-Physical Systems. Additional theory can be found in the Book: Logical Analysis of Hybrid Systems. Those books do not cover KeYmaera X specifically, though.
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