One-sided Heegaard splittings of RP^3

Using basic properties of one-sided Heegaard splittings, a direct proof that geometrically compressible one-sided splittings of RP^3 are stabilised is given. The argument is modelled on that used by Waldhausen to show that two-sided splittings of S^3 are standard.Comment: This is the version published by Algebraic & Geometric Topology on 20 September 200