A well-known reference site collecting researched UX laws and principles, from Fitts's Law to Hick's Law and beyond, each explained with its origin and practical implication.
Naming and citing the actual research behind a design decision when you need to justify it.
Designers who want to back up a UX call with a real, named principle.
Free, and available as a printed book/poster too.
Researched principles and laws that help guide the design process.
