1. Mechanical springs;Wahl,1963
2. Mechanics of materials;Timoshenko,1991
3. Pitch and curvature corrections for helical springs;Ancker;J Appl Mech,1958
4. Theory of pitch and curvature corrections for the helical springs-I (tension);Ancker;Trans ASME – J Appl Mech,1958
5. Theory of pitch and curvature corrections for the helical springs-II (torsion);Ancker;Trans ASME – J Appl Mech,1958