R. Hultberg

Rotary balance data for a typical single-engine low-wing general aviation design for an angle-of-attack range of 30 deg to 90 deg

W. Bihrle, W. Mulcay, R. S. Hultberg, 1978 .

Measurements of pressures on the tail and aft fuselage of an airplane model during rotary motions at spin attitudes

James S. Bowman, Colin A. Martin, Randy S. Hultberg, 1988 .