Andre's theory of spreads; spreads in PG(3,K); partial spreads and translation nets; spreadsheets and partial spreadsets; geometry of spreadsets; co-ordinatization by spreadsets - general cases; partial quasifields; co-ordinatization by (partial) quasifields; rational desarguesian nets; quasigroups, loops and nuclei; (pre)quasifields -algebraic axioms and autopisms; the kernel of spreadsets and quasifields; quadratics of two dimensional quasifields - Hall systems; spreads in projective spaces; kernel subplanes across Desarguesian nets; derivation of finite spreads; Foulser's covering theorem; structure of Baer groups; Frobenius complements, p-primitive collineations, and Klein-4 groups; large planar groups; finite generalized Andre systems and nearfields; elation net theory; Baer-elation theory; semifields. (Part contents).