Gholami , Raheb and Ansari , Reza. (2018). Size-Dependent Geometrically Nonlinear Free Vibration of First-Order Shear Deformable Piezoelectric-Piezomagnetic Nanobeams Using the Nonlocal Theory.
            <i>Advances in Applied Mathematics and Mechanics</i>. <i>10</i> (1).
            184-208.
         doi:10.4208/aamm.2015.m1298