1. Tobak, M. "On the Use of the Indicial Function Concept in the Analysis of Unsteady Motions of Wing and Wing-Tail Combinations," NACA Report 1188, 1954.
2. Computation of Unsteady Transonic Flows by the Indicial Method
3. Subsonic unsteady aerodynamics caused by gusts using the indicial method
4. Singh, R., Baeder, J.D. "The Direct Calculation of Indicial Lift Response Using Computational Fluid Dynamics," AIAA-96-2508.