Effects of warping function on scale-dependent torsional vibration of nano-bars Reza Hassannejad, Mir Mohammad Ettefagh and Babak Alizadeh-Hamidi Eur. Phys. J. Plus, 137 7 (2022) 794 Published online: 09 July 2022 DOI: 10.1140/epjp/s13360-022-03012-y