The conformal structures CO(4; 0);CO(1;3) and CO(2; 2) are studied on a real manifold M; dimM = 4. On M isotropic ber bundles E and E are constructed. These bundles are real for the CO(2; 2)-structure, and they satisfy the condition E = E for the CO(1; 3)-structure, and the conditions E = E; E = E for the CO(4)-structure. The tensor C of conformal curvature… (More)