Topological K-Theory

Some references on topological K-theory:

• Atiyah-Hirzebruch: Vector bundles and homogeneous spaces (1961)
• Milnor: Morse theory (1963)
• Atiyah: K-theory (1967)
• Hatcher: Vector Bundles & K-Theory https://www.math.cornell.edu/~hatcher/VBKT/VBpage.html