Dr. Bussard has posted several valuable documents on the Polywell fusion reactor, but there is no one source to obtain all of them. (besides the excellent Wikipedia article.)
So, to forestall the inevitable bit rot, here are some local copies.
"The Advent of Clean Nuclear Fusion: Super-performance Space Power and Propulsion" (4.6MiB .pdf) (from here)
"A quick history of the EMC2 Polywell IEF concept." (36KiB .doc) (from here)
"Inertial electrostatic fusion (IEF): A clean energy future." (48KiB .doc) (from here)