Author-hosted notes: people.math.harvard.edu/~mpopa/271/Kodaira-posted.pdf
Sections 1.1–1.3: plurigenera and birational invariance; Definition 1.2.1 and Proposition 1.2.4, Iitaka dimension and polynomial growth along sufficiently divisible powers; Definition 1.3.1 and Examples 1.3.2–1.3.7, Kodaira dimension and curve/surface examples.
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