Eltaher, M.A., Khairy, A., Sadoun, A.M., Omar, F.A. Static and buckling analysis of functionally graded Timoshenko nanobeams, Applied Mathematics and Computation, 229, 2014, pp. 283-295.
 Zhu, J., Lai, Z., Yin, Z., Jeon, J., Lee, S. Fabrication of ZrO 2–NiCr functionally graded material by powder metallurgy, Materials Chemistry and Physics, 68(1), 2001, pp. 130-135.
 Aqida, S.N., Ghazali, M.I., Hashim, J. Effects of porosity on mechanical properties of metal matrix composite: an overview, Jurnal Teknologi, 40, 2004, pp. 17-32.
 Kim, H.S., Yang, Y., Koh, J.T., Lee, K.K., Lee, D.J., Lee, K.M., Park, S.W. Fabrication and characterization of functionally graded nano‐micro porous titanium surface by anodizing, Journal of Biomedical Materials Research Part B: Applied Biomaterials, 88B, 2009, pp. 427-435.
 Wattanasakulpong, N., Prusty, B.G., Kelly, D.W., Hoffman, M. Free vibration analysis of layered functionally graded beams with experimental validation, Materials & Design, 36, 2012, pp. 182-190.
 Ji, S., Gu, Q., Xia, B. Porosity dependence of mechanical properties of solid materials, Journal of Materials Science, 41, 2006, pp. 1757-1768.
 Wattanasakulpong, N., Ungbhakorn, V. Linear and nonlinear vibration analysis of elastically restrained ends FGM beams with porosities, Aerospace Science and Technology, 32, 2014, pp. 111-120.
 Wattanasakulpong, N., Chaikittiratana, A. Flexural vibration of imperfect functionally graded beams based on Timoshenko beam theory, Chebyshev collocation method, Meccanica, 50(5), 2015, pp. 1331-1342.
 Atmane, H.A., Tounsi, A., Bernard, F. Effect of thickness stretching and porosity on mechanical response of a functionally graded beams resting on elastic foundations, International Journal of Mechanics and Materials in Design, 13, 2015, pp. 71-84.
 Ebrahimi, F., Mokhtari, M. Transverse vibration analysis of rotating porous beam with functionally graded microstructure using the differential transform method, Journal of the Brazilian Society of Mechanical Sciences and Engineering, 37, 2015, pp. 1435-1444.
 Ebrahimi, F., Jafari, A. A four-variable refined shear-deformation beam theory for thermo-mechanical vibration analysis of temperature-dependent FGM beams with porosities, Mechanics of Advanced Materials and Structures, 23, 2016, pp. 1-13.
 Ebrahimi, F., Ghasemi, F., Salari, E. Investigating thermal effects on vibration behavior of temperature-dependent compositionally graded Euler beams with porosities, Meccanica, 51, 2016, pp. 223-249.
 Shafiei, N., Mousavi, A., Ghadiri, M. On size-dependent nonlinear vibration of porous and imperfect functionally graded tapered microbeams, International Journal of Engineering Science, 106, 2016, pp. 42-56.
 Ebrahimi, F., Barati, M.R. Size-dependent vibration analysis of viscoelastic nanocrystalline silicon nanobeams with porosities based on a higher order refined beam theory, Composite Structures, 166, 2017, pp. 256-267.
 Magnucki, K., Stasiewicz, P. Elastic buckling of a porous beam, Journal of Theoretical and Applied Mechanics, 42(4), 2004, pp. 859-868.
 Jabbari, M., Mojahedin, A., Joubaneh, E.F. Thermal Buckling Analysis of Circular Plates Made of Piezoelectric and Saturated Porous Functionally Graded Material Layers, Journal of Engineering Mechanics, 141(4), 2015, pp. 1-12.
 Xue, L., Dui, G., Liu, B., Xin, L. A phenomenological constitutive model for functionally graded porous shape memory alloy, International Journal of Engineering Science, 78, 2014, pp. 103-113.
 Chen, D., Yang, J., Kitipornchai, S. Elastic buckling and static bending of shear deformable functionally graded porous beam, Composite Structures, 133, 2015, pp. 54-61.
 Kitipornchai, S., Chen, D., Yang, J., Free vibration and elastic buckling of functionally graded porous beams reinforced by graphene platelets, Materials & Design, 116, 2017, pp. 656-665.
 Hamed, M.A., Eltaher, M.A., Sadoun, A.M., Almitani, K.H. Free vibration of symmetric and sigmoid functionally graded nanobeams, Applied Physics A, 122(9), 2016, pp. 829-839.
 Ebrahimi, F., Zia, M., Large amplitude nonlinear vibration analysis of functionally graded Timoshenko beams with porosities, Acta Astronautica, 116, 2015, pp. 117-125.
 Sarkar, B.K., Mukherjee, M. K., Natarajan, A. A modification of the rule of mixture in estimating strengths of a composite, Materialwissenschaft und Werkstofftechnik, 13(8), 1982, pp. 269-273.
 Bert, C.W. Prediction of elastic moduli of solids with oriented porosity, Journal of Materials Science, 20(6), 1985, pp. 2220-2224.
 Hardin, R.A., Beckermann, C. Effect of porosity on the stiffness of cast steel, Metallurgical and Materials Transactions A, 38(12), 2007, pp. 2992-3006.
 Wachtman, J.B., Cannon, W.R., Matthewson, M.J. Mechanical properties of ceramics, John Wiley & Sons, New York, 2009.
 Sabree, I., Gough, J.E., Derby, B. Mechanical properties of porous ceramic scaffolds: influence of internal dimensions, Ceramics International, 41(7), 2015, pp. 8425-8432.
 Zok, F.W., Levi, C.G. Mechanical properties of porous-matrix ceramic composites, Advanced Engineering Materials, 3(1-2), 2001, pp. 15-23.
 Revel, G.M. Measurement of the apparent density of green ceramic tiles by a non-contact ultrasonic method, Experimental Mechanics, 47(5), 2007, pp. 637-648.
 Eltaher, M.A., Hamed, M.A., Sadoun, A.M., Mansour, A. Mechanical analysis of higher order gradient nanobeams, Applied Mathematics and Computation, 229, 2014, pp. 260-272.
 Alshorbagy A.E., Eltaher M.A., Mahmoud F.F. Free vibration characteristics of a functionally graded beam by finite element method, Applied Mathematical Modelling, 35(1), 2011, pp. 412–425.
 Eltaher, M.A., El-Borgi, S., Reddy, J.N. Nonlinear analysis of size-dependent and material-dependent nonlocal CNTs, Composite Structures, 153, 2016, pp. 902-913.